generic: keep module aliases inside .modinfo

It seems module aliases are actually essential info.  E.g. other modules
may call xt_request_find_match(NFPROTO_IPV{4,6}, "hashlimit", 1) and the
kernel will request user mode modprobe helper for ipt_hashlimit and
ip6t_hashlimit respectively which are aliases of xt_hashlimit.ko

Compile-tested for armvirt, there is nearly no size impact.

Before

    -rw-r--r-- 1 yousong yousong     304 Jan 10 17:37 config.seed
    -rw-r--r-- 1 yousong yousong    1634 Jan 11 11:07 lede-armvirt-default.manifest
    -rw-r--r-- 1 yousong yousong 1533647 Jan 11 11:07 lede-armvirt-default-rootfs.tar.gz
    -rw-r--r-- 1 yousong yousong 1802711 Jan 11 11:07 lede-armvirt-root.ext4.gz
    -rw-r--r-- 1 yousong yousong 1544597 Jan 11 11:07 lede-armvirt-rootfs.cpio.gz
    -rw-r--r-- 1 yousong yousong 1174984 Jan 11 11:07 lede-armvirt-root.squashfs.gz
    -rwxr-xr-x 1 yousong yousong 1654712 Jan 11 11:07 lede-armvirt-zImage
    -rwxr-xr-x 1 yousong yousong 2738296 Jan 11 11:07 lede-armvirt-zImage-initramfs
    drwxr-xr-x 2 yousong yousong    4096 Jan 10 17:35 packages
    -rw-r--r-- 1 yousong yousong     739 Jan 10 17:37 sha256sums

After

    -rw-r--r-- 1 yousong yousong     304 Jan 10 17:37 config.seed
    -rw-r--r-- 1 yousong yousong    1634 Jan 11 11:10 lede-armvirt-default.manifest
    -rw-r--r-- 1 yousong yousong 1533646 Jan 11 11:10 lede-armvirt-default-rootfs.tar.gz
    -rw-r--r-- 1 yousong yousong 1802711 Jan 11 11:10 lede-armvirt-root.ext4.gz
    -rw-r--r-- 1 yousong yousong 1544593 Jan 11 11:10 lede-armvirt-rootfs.cpio.gz
    -rw-r--r-- 1 yousong yousong 1174984 Jan 11 11:10 lede-armvirt-root.squashfs.gz
    -rwxr-xr-x 1 yousong yousong 1654736 Jan 11 11:10 lede-armvirt-zImage
    -rwxr-xr-x 1 yousong yousong 2738144 Jan 11 11:10 lede-armvirt-zImage-initramfs
    drwxr-xr-x 2 yousong yousong    4096 Jan 10 17:35 packages
    -rw-r--r-- 1 yousong yousong     739 Jan 10 17:37 sha256sums

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

target/linux/generic/patches-3.18/204-module_strip.patch

@@ -5,18 +5,14 @@ Signed-off-by: Felix Fietkau <nbd@nbd.name>
 ---
 --- a/include/linux/module.h
 +++ b/include/linux/module.h
-@@ -84,9 +84,10 @@ void trim_init_extable(struct module *m)
+@@ -84,6 +84,7 @@ void trim_init_extable(struct module *m)
  
  /* Generic info of form tag = "info" */
  #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
 +#define MODULE_INFO_STRIP(tag, info) __MODULE_INFO_STRIP(tag, tag, info)
  
  /* For userspace: you can also call me... */
--#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
-+#define MODULE_ALIAS(_alias) MODULE_INFO_STRIP(alias, _alias)
- 
- /* Soft module dependencies. See man modprobe.d for details.
-  * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
+ #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
 @@ -127,12 +128,12 @@ void trim_init_extable(struct module *m)
   * Author(s), use "Name <email>" or just "Name", for multiple
   * authors use multiple MODULE_AUTHOR() statements/lines.

target/linux/generic/patches-4.4/204-module_strip.patch

@@ -5,18 +5,14 @@ Signed-off-by: Felix Fietkau <nbd@nbd.name>
 ---
 --- a/include/linux/module.h
 +++ b/include/linux/module.h
-@@ -169,9 +169,10 @@ void trim_init_extable(struct module *m)
+@@ -169,6 +169,7 @@ void trim_init_extable(struct module *m)
  
  /* Generic info of form tag = "info" */
  #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
 +#define MODULE_INFO_STRIP(tag, info) __MODULE_INFO_STRIP(tag, tag, info)
  
  /* For userspace: you can also call me... */
--#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
-+#define MODULE_ALIAS(_alias) MODULE_INFO_STRIP(alias, _alias)
- 
- /* Soft module dependencies. See man modprobe.d for details.
-  * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
+ #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
 @@ -212,12 +213,12 @@ void trim_init_extable(struct module *m)
   * Author(s), use "Name <email>" or just "Name", for multiple
   * authors use multiple MODULE_AUTHOR() statements/lines.