gollvm: adapt libgo cmake rules for runtime.memmove

Fix up the libgo cmake rules to include go-memmove.c, following
the advent of https://golang.org/cl/294931.

Change-Id: Ia31d4afc23347f23eaa257635f11d5ab2c849094
Reviewed-on: https://go-review.googlesource.com/c/gollvm/+/300073
Trust: Than McIntosh <thanm@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/libgo/CMakeLists.txt b/libgo/CMakeLists.txt
index 0b6cf85..26e32b6 100644
--- a/libgo/CMakeLists.txt
+++ b/libgo/CMakeLists.txt
@@ -441,6 +441,7 @@
   "runtime/go-matherr.c"
   "runtime/go-memclr.c"
   "runtime/go-memequal.c"
+  "runtime/go-memmove.c"
   "runtime/go-nanotime.c"
   "runtime/go-now.c"
   "runtime/go-nosys.c"