parisc: enhance automatic CONFIG_CROSS_COMPILE detection

The current Makefile will only choose the hppa64 cross compiler when
running natively on hppa in a 32bit userspace.
This patch additionally chooses the correct 32/64 bit hppa compiler even
when doing real cross compiling to hppa/hppa64 from another architecture.
Signed-off-by: NHelge Deller <deller@gmx.de>

arch/parisc/Makefile

@@ -32,11 +32,6 @@ ifdef CONFIG_64BIT
 UTS_MACHINE	:= parisc64
 CHECKFLAGS	+= -D__LP64__=1 -m64
 WIDTH		:= 64
-
-# FIXME: if no default set, should really try to locate dynamically
-ifeq ($(CROSS_COMPILE),)
-CROSS_COMPILE	:= hppa64-linux-gnu-
-endif
 else # 32-bit
 WIDTH		:=
 endif
@@ -44,6 +39,10 @@ endif
 # attempt to help out folks who are cross-compiling
 ifeq ($(NATIVE),1)
 CROSS_COMPILE	:= hppa$(WIDTH)-linux-
+else
+ ifeq ($(CROSS_COMPILE),)
+ CROSS_COMPILE	:= hppa$(WIDTH)-linux-gnu-
+ endif
 endif
 
 OBJCOPY_FLAGS =-O binary -R .note -R .comment -S