[PARISC] Fix unwinder on 64-bit kernels

The unwinder was broken by the shift of PAGE_OFFSET in order to increase the
size of the vmalloc area on 64-bit kernels.

Signed-off-by: Randolph Chung <tausq@debian.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c
index e70f57e..cad9d78 100644
--- a/arch/parisc/kernel/unwind.c
+++ b/arch/parisc/kernel/unwind.c
@@ -26,6 +26,8 @@
 #define dbg(x...)
 #endif
 
+#define KERNEL_START (KERNEL_BINARY_TEXT_START - 0x1000)
+
 extern struct unwind_table_entry __start___unwind[];
 extern struct unwind_table_entry __stop___unwind[];