adb: avoid compilation errors for unused results

The BIO_CTRL_FLUSH function for files doesn't return anything useful
from the underlying fflush call, so it is safe to ignore this.

Change-Id: If33a7efbbaaf158e3da1cd72d0a56da1d3b82fd9
Merge "adb: avoid compilation errors for unused results"
Set kernel proc files for fwmark reflection and table numbers for RAs.

(cherry picked from commit 2c2807ac1041751583e0c3b6892ca56eae423fa2)

Change-Id: I5f0d759cb9b8590555af7f5503f00d3e455ece54
Merge "Set kernel proc files for fwmark reflection and table numbers for RAs."
auto-merger: merge in from aosp/master