msm_perf: fix warnings to enable msm_perf

Handle error checks in reading attributes.

Change-Id: I12b693e469b8a8de21a2bef36c92a012e5a2c034
Signed-off-by: Kishore Sri venkata Ganesh Bolisetty <quic_bsrivenk@quicinc.com>
[dereference23: Backport to msm-5.4]
Signed-off-by: Alexander Winkowski <dereference23@outlook.com>