msm: rpm_resources: Disable L2 SPM when msm_rpmrs_flush_buffer fails.

When rpmrs_flush_buffer fails, L2 SPM has to be disabled. Otherwise, it
could result in L2 being power collapsed when the Cores subsequently
enter clock gating mode. During clock gating, the L2 doesn't get
flushed, there by resulting in a crash if L2 SPM isn't disabled.

Change-Id: I21fb81cac6085bed2e5fc703add9721ae1093e2c
Signed-off-by: Mahesh Sivasubramanian <msivasub@codeaurora.org>