c2a: Crate: Don't parse -Wclippy, -D, and -W flags

Don't fail the generation of the Android.bp file when those flags are
encountered.

Bug: 243662244
Test: Used on gdbstub, which fixed issues seen in aosp/2191020
Change-Id: I80a6ecd8df7980234552a98ddb1149dc29542ac7
1 file changed