Retry adjusting the size computation for reserved blocks.
Due to the change in https://lwn.net/Articles/546473/, kernel reserves a
few extra blocks (lesser of 2% and 4096 blocks) on ext4 FS which leads to
OTA update failures. Adjust the size computation if the device has
BOARD_HAS_EXT4_RESERVED_BLOCKS := true.
It amends the last attemp in [1]. Now it computes the used blocks from the
make_ext4fs output, instead of altering its argument.
[1]: commit
efbb5d2e692283be32069e808b88522727c7fe98.
Bug:
21522719
Bug:
22023465
Bug:
22174684
Change-Id: I9783a51abe6581ff5c75db81e78ac606d0f32c4c