NFC: st95hf: Fix build error

This fixes a build error on the mn10300 architecture:

drivers/nfc/st95hf/core.c:765:20: error: conflicting types for 'irq_handler'
   static irqreturn_t irq_handler(int irq, void  *st95hfcontext)
                       ^
   In file included from arch/mn10300/include/asm/reset-regs.h:16:0,
                    from arch/mn10300/include/asm/irq.h:18,
                    from include/linux/irq.h:26,
                    from arch/mn10300/include/asm/hardirq.h:16,
                    from include/linux/hardirq.h:8,
                    from include/linux/interrupt.h:12,
                    from drivers/nfc/st95hf/core.c:23:
   arch/mn10300/include/asm/exceptions.h:107:24: note: previous declaration of 'irq_handler' was here
    extern asmlinkage void irq_handler(void);
Signed-off-by: Shikha Singh <shikha.singh@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/nfc/st95hf/core.c

@@ -762,7 +762,7 @@ static int st95hf_response_handler(struct st95hf_context *stcontext,
 	return result;
 }
 
-static irqreturn_t irq_handler(int irq, void  *st95hfcontext)
+static irqreturn_t st95hf_irq_handler(int irq, void  *st95hfcontext)
 {
 	struct st95hf_context *stcontext  =
 		(struct st95hf_context *)st95hfcontext;
@@ -776,7 +776,7 @@ static irqreturn_t irq_handler(int irq, void  *st95hfcontext)
 	return IRQ_WAKE_THREAD;
 }
 
-static irqreturn_t irq_thread_handler(int irq, void  *st95hfcontext)
+static irqreturn_t st95hf_irq_thread_handler(int irq, void  *st95hfcontext)
 {
 	int result = 0;
 	int res_len;
@@ -1140,8 +1140,8 @@ static int st95hf_probe(struct spi_device *nfc_spi_dev)
 	if (nfc_spi_dev->irq > 0) {
 		if (devm_request_threaded_irq(&nfc_spi_dev->dev,
 					      nfc_spi_dev->irq,
-					      irq_handler,
-					      irq_thread_handler,
+					      st95hf_irq_handler,
+					      st95hf_irq_thread_handler,
 					      IRQF_TRIGGER_FALLING,
 					      "st95hf",
 					      (void *)st95context) < 0) {