Revert "ramips: fix flash layout for TP-Link TL-WR841N v14"

This reverts commit 1623defbdb.

As already stated in the reverted patch, the OEM firmware will
properly recreate the config partition if it is overwritten by
OpenWrt.

The main reason for adding the partition was the image size
restriction imposed by the 0x3d0000 limitation of the TFTP
flashing process. Addressing this by shrinking the firmware
partition is not a good solution to that problem, though:

1. For a working image, the size of the content has to be smaller
   than the available space, so empty erase blocks will remain.

2. Conceptually, the restriction is on the image, so it makes sense
   to implement it in the same way, and not via the partitioning.
   Users could e.g. do initial flash with TFTP restriction with
   an older image, and then sysupgrade into a newer one, so TFTP
   restriction does not apply.

3. The (content) size of the recovery image is enforced to 0x3d0000
   by the tplink-v2-image command in combination with
   TPLINK_FLASHLAYOUT (flash layout in mktplinkfw2.c) anyway.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

target/linux/ramips/dts/mt7628an_tplink_tl-wr841n-v14.dts

@@ -81,13 +81,7 @@
 			partition@10000 {
 				compatible = "tplink,firmware";
 				label = "firmware";
-				reg = <0x10000 0x3d0000>;
-			};
-
-			partition@3e0000 {
-				label = "config";
-				reg = <0x3e0000 0x10000>;
-				read-only;
+				reg = <0x10000 0x3e0000>;
 			};
 
 			factory: partition@3f0000 {

target/linux/ramips/image/mt76x8.mk

@@ -498,7 +498,7 @@ TARGET_DEVICES += tplink_tl-wr841n-v13
 
 define Device/tplink_tl-wr841n-v14
   $(Device/tplink-v2)
-  IMAGE_SIZE := 3904k
+  IMAGE_SIZE := 3968k
   DEVICE_MODEL := TL-WR841N
   DEVICE_VARIANT := v14
   TPLINK_FLASHLAYOUT := 4Mmtk