xtensa: merge stack alignment definitions

xtensa currently has two different definitions for stack alignment.
Replace it with single definition usable in both C and assembly.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/include/asm/asmmacro.h

@@ -225,8 +225,6 @@
 #endif
 	.endm
 
-#define XTENSA_STACK_ALIGNMENT		16
-
 #if defined(__XTENSA_WINDOWED_ABI__)
 
 /* Assembly instructions for windowed kernel ABI. */

arch/xtensa/include/asm/core.h

@@ -37,4 +37,11 @@
 #endif
 #endif
 
+/* Xtensa ABI requires stack alignment to be at least 16 */
+#if XCHAL_DATA_WIDTH > 16
+#define XTENSA_STACK_ALIGNMENT	XCHAL_DATA_WIDTH
+#else
+#define XTENSA_STACK_ALIGNMENT	16
+#endif
+
 #endif

arch/xtensa/include/asm/processor.h

@@ -18,11 +18,7 @@
 #include <asm/types.h>
 #include <asm/regs.h>
 
-/* Xtensa ABI requires stack alignment to be at least 16 */
-
-#define STACK_ALIGN (XCHAL_DATA_WIDTH > 16 ? XCHAL_DATA_WIDTH : 16)
-
-#define ARCH_SLAB_MINALIGN STACK_ALIGN
+#define ARCH_SLAB_MINALIGN XTENSA_STACK_ALIGNMENT
 
 /*
  * User space process size: 1 GB.