LU-11215 tests: replace "large_xattr" with "ea_inode"

LU-11215 tests: replace "large_xattr" with "ea_inode"

Change the test scripts over to using the "ea_inode" name, since
this is what the upstream e2fsprogs is using.  The "large_xattr"
feature name was only ever used in the Lustre-patched e2fsprogs.

Don't try to turn off "ea_inode" feature on the targets anymore,
it's not supported by upstream e2fsprogs.

e2fsprogs commit: 5b72578279fe2470e682692a15d70a43d9289e0f

This patch is back-ported from the following one:
Lustre-commit: 900a1b6e4271a6c1903d6723082a01c98defe7b2
Lustre-change: https://review.whamcloud.com/33012

Test-Parameters: trivial testlist=conf-sanity
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Li Dongyang <dongyangli@ddn.com>
Change-Id: I83bd303827fa28050d1d6d2416b2d630dc94ec12
Reviewed-on: https://review.whamcloud.com/33503
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <jhammond@whamcloud.com>