arch/*: Update Kconfig symbol usage

- Update all symbols to use IS_ENABLED()
- Update non-romcc usage to use 'if' instead of '#if' where it
makes sense.

Change-Id: I5a84414d2d1631e35ac91efb67a0d4c1f673bf85
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/20005
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/arch/arm/include/armv7/arch/cache.h

@@ -134,12 +134,11 @@ static inline void write_mair0(uint32_t val)
 /* write translation table base register 0 (TTBR0) */
 static inline void write_ttbr0(uint32_t val)
 {
-#if CONFIG_ARM_LPAE
-	asm volatile ("mcrr p15, 0, %[val], %[zero], c2" : :
+	if (IS_ENABLED(CONFIG_ARM_LPAE))
+		asm volatile ("mcrr p15, 0, %[val], %[zero], c2" : :
 			[val] "r" (val), [zero] "r" (0));
-#else
-	asm volatile ("mcr p15, 0, %0, c2, c0, 0" : : "r" (val) : "memory");
-#endif
+	else
+		asm volatile ("mcr p15, 0, %0, c2, c0, 0" : : "r" (val) : "memory");
 }
 
 /* read translation table base control register (TTBCR) */

src/arch/arm/include/armv7/arch/cpu.h

@@ -33,7 +33,7 @@ struct thread;
 struct cpu_info {
 	device_t cpu;
 	unsigned long index;
-#if CONFIG_COOP_MULTITASKING
+#if IS_ENABLED(CONFIG_COOP_MULTITASKING)
 	struct thread *thread;
 #endif
 };