arch/tile: mark TILEGX as not EXPERIMENTAL

Also create a TILEPRO config setting to use for #ifdefs where it
is cleaner to do so, and make the 64BIT setting depend directly
on the setting of TILEGX.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index cc56642..0294b21 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -117,16 +117,14 @@
 	select HVC_DRIVER
 	def_bool y
 
-# Please note: TILE-Gx support is not yet finalized; this is
-# the preliminary support.  TILE-Gx drivers are only provided
-# with the alpha or beta test versions for Tilera customers.
 config TILEGX
-	depends on EXPERIMENTAL
 	bool "Building with TILE-Gx (64-bit) compiler and toolchain"
 
+config TILEPRO
+	def_bool !TILEGX
+
 config 64BIT
-	depends on TILEGX
-	def_bool y
+	def_bool TILEGX
 
 config ARCH_DEFCONFIG
 	string