mediatek: mt7622: drop RAMFS_COPY_BIN and RAMFS_COPY_DATA

Now that both, fw_printenv/fw_setenv and fwtool are always present
during stage2 sysupgrade, we no longer need to list them in
RAMFS_COPY_BIN and RAMFS_COPY_DATA in platform.sh.
Drop both variables as they are now unneeded.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

target/linux/mediatek/mt7622/base-files/lib/upgrade/platform.sh

 REQUIRE_IMAGE_METADATA=1
-RAMFS_COPY_BIN='fw_printenv fw_setenv fwtool'
-RAMFS_COPY_DATA='/etc/fw_env.config /var/lock/fw_printenv.lock'
 
 platform_do_upgrade() {
 	local board=$(board_name)