x86: OLPC: Remove extra OLPC_OPENFIRMWARE_DT indirection

OLPC_OPENFIRMWARE_DT is just there to be selected by OLPC and selects
OF_PROMTREE. So let OLPC select OF_PROMTREE and remove that extra
config indirection. Fixup code and Makefile and use CONFIG_OF_PROMTREE
instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andres Salomon <dilinger@queued.net>

arch/x86/Kconfig

@@ -2069,7 +2069,7 @@ config OLPC
 	depends on !X86_PAE
 	select GPIOLIB
 	select OF
-	select OLPC_OPENFIRMWARE_DT if PROC_DEVICETREE
+	select OF_PROMTREE if PROC_DEVICETREE
 	---help---
 	  Add support for detecting the unique features of the OLPC
 	  XO hardware.
@@ -2080,10 +2080,6 @@ config OLPC_XO1
 	---help---
 	  Add support for non-essential features of the OLPC XO-1 laptop.
 
-config OLPC_OPENFIRMWARE_DT
-	bool
-	select OF_PROMTREE
-
 endif # X86_32
 
 config AMD_NB

arch/x86/include/asm/olpc_ofw.h

@@ -24,10 +24,10 @@ extern void setup_olpc_ofw_pgd(void);
 /* check if OFW was detected during boot */
 extern bool olpc_ofw_present(void);
 
-#ifdef CONFIG_OLPC_OPENFIRMWARE_DT
+#ifdef CONFIG_OF_PROMTREE
 extern void olpc_dt_build_devicetree(void);
 #else
 static inline void olpc_dt_build_devicetree(void) { }
-#endif /* CONFIG_OLPC_OPENFIRMWARE_DT */
+#endif
 
 #endif /* _ASM_X86_OLPC_OFW_H */

arch/x86/platform/olpc/Makefile

 obj-$(CONFIG_OLPC)		+= olpc.o
 obj-$(CONFIG_OLPC_XO1)		+= olpc-xo1.o
 obj-$(CONFIG_OLPC)		+= olpc_ofw.o
-obj-$(CONFIG_OLPC_OPENFIRMWARE_DT)	+= olpc_dt.o
+obj-$(CONFIG_OF_PROMTREE)	+= olpc_dt.o