fstools: add direct dependencies on libblobmsg-json and libjson-c

The OpenWrt buildroot ABI version rebuild tracker does not handle
transient dependencies, therefore add all libraries linked by
block-mount and blockd as direct dependencies to the corresponding
binary package definition.

This ensures that block-mount and blockd is automatically rebuilt and
relinked if any of these libraries has its ABI_VERSION updated in the
future.

Fixes: FS#2373
[jow: similar fix for procd and 98.42% of commit message]
Signed-off-by: Jo-Philip Wich <jow@mein.io>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
(cherry picked from commit cbae306815bdfc335eeedc35dc5df3d2d4021a2a)

package/system/fstools/Makefile

@@ -79,14 +79,14 @@ define Package/block-mount
   SECTION:=base
   CATEGORY:=Base system
   TITLE:=Block device mounting and checking
-  DEPENDS:=+ubox +libubox +libuci
+  DEPENDS:=+ubox +libubox +libuci +libblobmsg-json +libjson-c
 endef
 
 define Package/blockd
   SECTION:=base
   CATEGORY:=Base system
   TITLE:=Block device automounting
-  DEPENDS:=+block-mount +fstools +libubus +kmod-fs-autofs4
+  DEPENDS:=+block-mount +fstools +libubus +kmod-fs-autofs4 +libblobmsg-json +libjson-c
 endef
 
 define Package/fstools/install