Some more cleanup which should've been in r6232. Thanks Billiard.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6234 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/Core/Src/PowerPC/Jit64/Jit_LoadStore.cpp

@@ -413,7 +413,7 @@ void Jit64::stXx(UGeckoInstruction inst)
 		MOV(32, R(EDX), gpr.R(a));
 		ADD(32, R(EDX), gpr.R(b));
 	}
-	unsigned accessSize;
+	int accessSize;
 	switch (inst.SUBOP10 & ~32) {
 		case 151: accessSize = 32; break;
 		case 407: accessSize = 16; break;