ext4: check buffer_verified in advance to avoid unneeded ext4_get_group_info()

Check buffer_verified in advance to avoid unneeded ext4_get_group_info().
This could be a simple cleanup as compiler may handle this.

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Link: https://patch.msgid.link/20240820132234.2759926-8-shikemeng@huaweicloud.com


Signed-off-by: Theodore Ts'o <tytso@mit.edu>