sepolicy: Add libsc-a3xx to SPHAL namespace

Add libsc-a3xx.so lib to SPHAL namespace for ms8909 & msm8917
Denial:
01-06 04:18:03.849  1401  1401 I auditd  : type=1400 audit(0.0:127):
avc: denied { read } for comm="surfaceflinger" name="libsc-a3xx.so"
dev="mmcblk0p25" ino=2010 scontext=u:r:surfaceflinger:s0
tcontext=u:object_r:vendor_file:s0 tclass=file permissive=0

Change-Id: I098ee1277c9b805cc43f46700351d81d60f0fdbf