Specify osabi in arm/aarch64 tdescs.

Upstream probably won't like this. Presumably, the correct fix is to add
a new -linux version of each of these.

Bug: http://b/27926981
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=19895
Change-Id: I1eb1d821b027e18c152f025768e2c4d24f3d2729
10 files changed
tree: b573c84ca9e8f80cb04367932fcd059063a20a88
  1. gdb-7.11/
  2. build-gdb.sh
  3. build.py