[][openwrt][common][bsp][Refactor dual image related patches]

[Description]
Refactor dual image related patches:
1. merge chunks.
2. Move patches to same folder

[Release-log]
N/A

Change-Id: I3f30642b70e3db85d6e25eba85454bf257484bd4
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/8823084
diff --git a/21.02/files/target/linux/generic/hack-5.4/999-2540-cmdline-boot-parameters.patch b/21.02/files/target/linux/mediatek/patches-5.4/999-2540-cmdline-boot-parameters.patch
similarity index 98%
rename from 21.02/files/target/linux/generic/hack-5.4/999-2540-cmdline-boot-parameters.patch
rename to 21.02/files/target/linux/mediatek/patches-5.4/999-2540-cmdline-boot-parameters.patch
index eadc288..1eb437c 100644
--- a/21.02/files/target/linux/generic/hack-5.4/999-2540-cmdline-boot-parameters.patch
+++ b/21.02/files/target/linux/mediatek/patches-5.4/999-2540-cmdline-boot-parameters.patch
@@ -40,7 +40,7 @@
 +
 +#define BOOT_PARAM_STR_MAX_LEN			256
 +
-+static bool dual_boot;
++bool dual_boot;
 +module_param(dual_boot, bool, 0444);
 +
 +static bool no_split_rootfs_data;
diff --git a/21.02/files/target/linux/mediatek/patches-5.4/999-2550-dual-image-mount-rootfs.patch b/21.02/files/target/linux/mediatek/patches-5.4/999-2550-dual-image-mount-rootfs.patch
index 350e7d3..48b94cd 100644
--- a/21.02/files/target/linux/mediatek/patches-5.4/999-2550-dual-image-mount-rootfs.patch
+++ b/21.02/files/target/linux/mediatek/patches-5.4/999-2550-dual-image-mount-rootfs.patch
@@ -22,19 +22,6 @@
  		return;
  #endif
  #ifdef CONFIG_BLOCK
-diff --git a/kernel/boot_param.c b/kernel/boot_param.c
-index 3dfe828bc..cc0b2b8b0 100644
---- a/kernel/boot_param.c
-+++ b/kernel/boot_param.c
-@@ -10,7 +10,7 @@
- 
- #define BOOT_PARAM_STR_MAX_LEN			256
- 
--static bool dual_boot;
-+bool dual_boot;
- module_param(dual_boot, bool, 0444);
- 
- static bool no_split_rootfs_data;
 -- 
 2.34.1