parisc: Fix boot failure of 64-bit kernel

Commit c8921d72e3 ("parisc: Fix and improve kernel stack unwinding")
broke booting of 64-bit kernels. On 64-bit kernels function pointers are
actually function descriptors which require dereferencing. In this patch
we instead declare functions in assembly code which are referenced from
C-code as external data pointers with the ENTRY() macro and thus can use
a simple external reference to the functions.

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: c8921d72e3 ("parisc: Fix and improve kernel stack unwinding")

arch/parisc/include/asm/linkage.h

@@ -22,15 +22,6 @@
 name:		ASM_NL\
 	.export name
 
-#ifdef CONFIG_64BIT
-#define ENDPROC(name) \
-	END(name)
-#else
-#define ENDPROC(name) \
-	.type name, @function !\
-	END(name)
-#endif
-
 #define ENTRY_CFI(name, ...) \
 	ENTRY(name)	ASM_NL\
 	.proc		ASM_NL\