parisc/unaligned: Fix emulate_ldw() breakage

The commit e8aa7b17 broke the 32-bit load-word unalignment exception
handler because it calculated the wrong amount of bits by which the value
should be shifted. This patch fixes it.
Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: e8aa7b17 ("parisc/unaligned: Rewrite inline assembly of emulate_ldw()")
Cc: stable@vger.kernel.org   # v5.18

arch/parisc/kernel/unaligned.c

@@ -146,7 +146,7 @@ static int emulate_ldw(struct pt_regs *regs, int toreg, int flop)
 "	depw	%%r0,31,2,%4\n"
 "1:	ldw	0(%%sr1,%4),%0\n"
 "2:	ldw	4(%%sr1,%4),%3\n"
-"	subi	32,%4,%2\n"
+"	subi	32,%2,%2\n"
 "	mtctl	%2,11\n"
 "	vshd	%0,%3,%0\n"
 "3:	\n"