LU-10038 test: improve error reporting in sanity test_133g()

LU-10038 test: improve error reporting in sanity test_133g()

In sanity test_133g() remove the output redirection to /dev/null so
that errors from do_facet or find go to the test logs. Suppress error
messages in badarea_io.c.

Test-Parameters: trivial envdefinitions=ONLY=133 testlist=sanity,sanity,sanity,sanity,sanity,sanity,sanity,sanity,sanity,sanity
Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: Ia51ccdacb995ff51a6467cbdd280c8965cfc5f47
Reviewed-on: https://review.whamcloud.com/30219
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>