libgo: fix makefile buglet

Fix a small bug in the libgo Makefile recipe that constructs the
directory from which to pick up libgcc_s.so ; the gccgo invocation
with -print-libgcc-file-name was missing the flags, which meant that
for -m32 builds we'd see the 64-bit libgcc dir.

Change-Id: I0ec85d977e2b1a5ab13149456b5d0666d714c3ee
Reviewed-on: https://go-review.googlesource.com/78836
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2 files changed