nir: move shader_enums.[ch] to compiler

This way one can reuse it in glsl, nir or other infrastructure without
pulling nir as dependency.

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Matt Turner <mattst88@gmail.com>
Acked-by: Jose Fonseca <jfonseca@vmware.com>

src/compiler/SConscript

@@ -0,0 +1,22 @@
+Import('*')
+
+env = env.Clone()
+
+env.MSVC2013Compat()
+
+env.Prepend(CPPPATH = [
+    '#include',
+    '#src',
+    '#src/mapi',
+    '#src/mesa',
+    '#src/gallium/include',
+    '#src/gallium/auxiliary',
+])
+
+sources = env.ParseSourceList('Makefile.sources', 'LIBCOMPILER_FILES')
+
+compiler = env.ConvenienceLibrary(
+    target = 'compiler',
+    source = sources
+)
+Export('compiler')