r600g: fix build without opencl and static llvm libs

radeon_llvm_check and friends were never called in the no-opencl case,
which ended up with an empty llvm module list. As --enable-opencl always
requires --enable-llvm, we can use the latter as the guard.

Signed-off-by: Marc Dietrich <marvin24@gmx.de>
[Emil Velikov: commit message polish]
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
diff --git a/configure.ac b/configure.ac
index 890a379..a3d1a00 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2297,7 +2297,7 @@
             HAVE_GALLIUM_R600=yes
             PKG_CHECK_MODULES([RADEON], [libdrm >= $LIBDRM_RADEON_REQUIRED libdrm_radeon >= $LIBDRM_RADEON_REQUIRED])
             require_libdrm "r600"
-            if test "x$enable_opencl" = xyes; then
+            if test "x$enable_llvm" = xyes; then
                 radeon_llvm_check $LLVM_REQUIRED_R600 "r600"
 
                 llvm_add_component "asmparser" "r600"