MA-17142-2 set metadata partition type as ext4

MA-17142-2 set metadata partition type as ext4

metadata partition is used in some functions like apex, userdata
checkpoint to store files, mark it as ext4 partition so it can be
formated with "fastboot format metadata" command and be mounted when
executing first stage init.

Change-Id: Id22b39d71e6823d3a284f3df00959a6d748ab9c7
Signed-off-by: faqiang.zhu <faqiang.zhu@nxp.com>
(cherry picked from commit 4f42888967a0354a0dd222ad7b01761450a1713b)
(cherry picked from commit a69157bee180974eb4ee89b0847473bd6538d2a0)