ARM: 8215/1: vfp: Silence mvfr0 variable unused warning

Stephen Rothwell reports that commit 3f4c9f8f0a20 ("ARM: 8197/1:
vfp: Fix VFPv3 hwcap detection on CPUID based cpus") introduced a
variable unused warning.

arch/arm/vfp/vfpmodule.c: In function 'vfp_init':
arch/arm/vfp/vfpmodule.c:725:6: warning: unused variable 'mvfr0'
[-Wunused-variable]
  u32 mvfr0;

Silence this warning by using IS_ENABLED instead of ifdefs.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/vfp/vfpmodule.c

@@ -722,7 +722,6 @@ static int __init vfp_init(void)
 {
 	unsigned int vfpsid;
 	unsigned int cpu_arch = cpu_architecture();
-	u32 mvfr0;
 
 	if (cpu_arch >= CPU_ARCH_ARMv6)
 		on_each_cpu(vfp_enable, NULL, 1);
@@ -752,12 +751,12 @@ static int __init vfp_init(void)
 		 * precision floating point operations. Only check
 		 * for NEON if the hardware has the MVFR registers.
 		 */
-#ifdef CONFIG_NEON
-		if ((fmrx(MVFR1) & 0x000fff00) == 0x00011100)
+		if (IS_ENABLED(CONFIG_NEON) &&
+		   (fmrx(MVFR1) & 0x000fff00) == 0x00011100)
 			elf_hwcap |= HWCAP_NEON;
-#endif
-#ifdef CONFIG_VFPv3
-		mvfr0 = fmrx(MVFR0);
+
+		if (IS_ENABLED(CONFIG_VFPv3)) {
+			u32 mvfr0 = fmrx(MVFR0);
 			if (((mvfr0 & MVFR0_DP_MASK) >> MVFR0_DP_BIT) == 0x2 ||
 			    ((mvfr0 & MVFR0_SP_MASK) >> MVFR0_SP_BIT) == 0x2) {
 				elf_hwcap |= HWCAP_VFPv3;
@@ -775,7 +774,7 @@ static int __init vfp_init(void)
 
 			if ((fmrx(MVFR1) & 0xf0000000) == 0x10000000)
 				elf_hwcap |= HWCAP_VFPv4;
-#endif
+		}
 	/* Extract the architecture version on pre-cpuid scheme */
 	} else {
 		if (vfpsid & FPSID_NODOUBLE) {