[ARM] pxa/vpac270: remove TS_IRQ magic number

The touchscreen GPIO IRQ was used as a magic number. Define it properly in the
board header file. This is a simple cleanup patch.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
diff --git a/arch/arm/mach-pxa/vpac270.c b/arch/arm/mach-pxa/vpac270.c
index 6575b8f..a1b39c4 100644
--- a/arch/arm/mach-pxa/vpac270.c
+++ b/arch/arm/mach-pxa/vpac270.c
@@ -388,7 +388,7 @@
 };
 
 static struct ucb1400_pdata vpac270_ucb1400_pdata = {
-	.irq		= IRQ_GPIO(113),
+	.irq		= IRQ_GPIO(GPIO113_VPAC270_TS_IRQ),
 };
 
 static struct platform_device vpac270_ucb1400_device = {