ramips: mt7621: enable lzma-loader for some devices

ubnt er-x/xiaomi/netgear sercomm devices are known to have troble
extracting a big kernel from flash and has support for uncompressed
uimage
This commit uses uncompressed uimage with lzma-loader for these devices
to fix boot issue.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>

target/linux/ramips/image/mt7621.mk

@@ -565,6 +565,7 @@ endef
 TARGET_DEVICES += netgear_ex6150
 
 define Device/netgear_sercomm_nand
+  $(Device/uimage-lzma-loader)
   BLOCKSIZE := 128k
   PAGESIZE := 2048
   KERNEL_SIZE := 4096k
@@ -658,6 +659,7 @@ endef
 TARGET_DEVICES += netgear_r6850
 
 define Device/netgear_wndr3700-v5
+  $(Device/uimage-lzma-loader)
   BLOCKSIZE := 64k
   IMAGE_SIZE := 15232k
   SERCOMM_HWID := AYB
@@ -794,6 +796,7 @@ endef
 TARGET_DEVICES += tplink_re650-v1
 
 define Device/ubnt_edgerouter_common
+  $(Device/uimage-lzma-loader)
   DEVICE_VENDOR := Ubiquiti
   IMAGE_SIZE := 256768k
   FILESYSTEMS := squashfs
@@ -870,6 +873,7 @@ endef
 TARGET_DEVICES += wevo_w2914ns-v2
 
 define Device/xiaomi_mir3g
+  $(Device/uimage-lzma-loader)
   BLOCKSIZE := 128k
   PAGESIZE := 2048
   KERNEL_SIZE := 4096k
@@ -889,6 +893,7 @@ endef
 TARGET_DEVICES += xiaomi_mir3g
 
 define Device/xiaomi_mir3g-v2
+  $(Device/uimage-lzma-loader)
   IMAGE_SIZE := 14848k
   DEVICE_VENDOR := Xiaomi
   DEVICE_MODEL := Mi Router 3G
@@ -901,6 +906,7 @@ endef
 TARGET_DEVICES += xiaomi_mir3g-v2
 
 define Device/xiaomi_mir3p
+  $(Device/uimage-lzma-loader)
   BLOCKSIZE := 128k
   PAGESIZE := 2048
   KERNEL_SIZE:= 4096k