sepolicy: suppress denial logspam

These denials are not causing app bugs but the underlying code needs
to be fixed. In the meantime, remove them from the logs.

avc: denied { read } for name="/" dev="tmpfs" ino=19039
scontext=u:r:priv_app:s0:c512,c768 tcontext=u:object_r:device:s0
tclass=dir
avc: denied { read } for name="interrupts" dev="proc" ino=4026532104
scontext=u:r:priv_app:s0:c512,c768
tcontext=u:object_r:proc_interrupts:s0 tclass=file

Bug: 63631799
Test: Build and flash, verify denials are gone.
Change-Id: I6ddc91aa792b771e2c4190b211588347cc4119ea