[magma] Also switch gbm's dep to libmagma_virt

Bug:118657

Change-Id: Id13b0f97b96ee8ebcb12092e10e4166dd46901e5
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/mesa/+/786110
Reviewed-by: John Bauman <jbauman@google.com>
diff --git a/src/gbm/BUILD.gn b/src/gbm/BUILD.gn
index bd00ecc..1999033 100644
--- a/src/gbm/BUILD.gn
+++ b/src/gbm/BUILD.gn
@@ -19,7 +19,7 @@
   ]
 
   deps = [
-    "$magma_build_root/src/libmagma_linux",
+    "$magma_build_root/src/libmagma_virt",
   ]
 
   cflags_c = [ "-Wno-strict-prototypes" ]