mkuserimg: Add retry and display memory stats while generating image

Display memory stats to aid in debugging of out of memory
situations while generating ext4 images; and also attempt a
retry on failure.  This is a temporary workaround to track
OOM failures on shared build servers.
Change-Id: I1012ca2ab654ad1d47377b15be0d8372e8dc1520
Merge "mkuserimg: Add retry and display memory stats while generating image"
mkuserimg: Dump lsof in case of a image generation failure.

This is a temporary change required to look at the list of all
open files in case of a image generation failure job.

Change-Id: I33479bf159a54302b360f8825969753b28739c35
Merge pull request #1 from AOSParadox/LA.BF.1.1.2_rb1.10

CAF UPDATE : LA.BF.1.1.2_rb1.10