Fix version macros

Change-Id: I041a7a27e9166c383da169ac98eb600f509fe659
diff --git a/src/BUILD.gn b/src/BUILD.gn
index cec7e6d..23fa80f 100644
--- a/src/BUILD.gn
+++ b/src/BUILD.gn
@@ -22,6 +22,8 @@
 import("//garnet/lib/magma/gnbuild/magma.gni")
 
 config("common_config") {
+  mesa_version = read_file("../VERSION", "trim string")
+
   defines = [
     "STDC_HEADERS=1",
     "HAVE_SYS_TYPES_H=1",
@@ -58,12 +60,12 @@
     "HAVE_CLOCK_GETTIME=1",
     "PACKAGE_NAME=\"Mesa\" ",
     "PACKAGE_TARNAME=\"mesa\" ",
-    "PACKAGE_VERSION=\"11.2.1\" ",
-    "PACKAGE_STRING=\"Mesa\ 11.2.1\" ",
+    "PACKAGE_VERSION=\"$mesa_version\" ",
+    "PACKAGE_STRING=\"Mesa $mesa_version\" ",
     "PACKAGE_BUGREPORT=\"https://bugs.freedesktop.org/enter_bug.cgi\?product=Mesa\" ",
     "PACKAGE_URL=\"\" ",
     "PACKAGE=\"mesa\" ",
-    "VERSION=\"11.2.1\"",
+    "VERSION=\"$mesa_version\"",
     "_DEFAULT_SOURCE",
   ]