ext4: fix FITRIM in no journal mode

ext4: fix FITRIM in no journal mode

When using FITRIM ioctl on a file system without journal it will
only trim the block group once, no matter how many times you invoke
FITRIM ioctl and how many block you release from the block group.

It is because we only clear EXT4_GROUP_INFO_WAS_TRIMMED_BIT in journal
callback. Fix this by clearing the bit in no journal mode as well.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Jorge Fábregas <jorge.fabregas@gmail.com>