parisc: fix frame pointer in ftrace_regs_caller()

The current code in ftrace_regs_caller() doesn't assign
%r3 to contain the address of the current frame. This
is hidden if the kernel is compiled with FRAME_POINTER,
but without it just crashes because it tries to dereference
an arbitrary address. Fix this by always setting %r3 to the
current stack frame.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/kernel/entry.S

@@ -2125,7 +2125,7 @@ ftrace_regs_caller:
 	copy	%rp, %r26
 	LDREG	-FTRACE_FRAME_SIZE-PT_SZ_ALGN(%sp), %r25
 	ldo	-8(%r25), %r25
-	copy	%r3, %arg2
+	ldo	-FTRACE_FRAME_SIZE(%r1), %arg2
 	b,l	ftrace_function_trampoline, %rp
 	copy	%r1, %arg3 /* struct pt_regs */