arm64: move SEGMENT_ALIGN to <asm/memory.h>

Currently we define SEGMENT_ALIGN directly in our vmlinux.lds.S.

This is unfortunate, as the EFI stub currently open-codes the same
number, and in future we'll want to fiddle with this.

This patch moves the definition to our <asm/memory.h>, where it can be
used by both vmlinux.lds.S and the EFI stub code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 1fc2453..7fa6ad4 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -113,6 +113,25 @@
 #define IRQ_STACK_SIZE		THREAD_SIZE
 
 /*
+ * Alignment of kernel segments (e.g. .text, .data).
+ */
+#if defined(CONFIG_DEBUG_ALIGN_RODATA)
+/*
+ *  4 KB granule:   1 level 2 entry
+ * 16 KB granule: 128 level 3 entries, with contiguous bit
+ * 64 KB granule:  32 level 3 entries, with contiguous bit
+ */
+#define SEGMENT_ALIGN			SZ_2M
+#else
+/*
+ *  4 KB granule:  16 level 3 entries, with contiguous bit
+ * 16 KB granule:   4 level 3 entries, without contiguous bit
+ * 64 KB granule:   1 level 3 entry
+ */
+#define SEGMENT_ALIGN			SZ_64K
+#endif
+
+/*
  * Memory types available.
  */
 #define MT_DEVICE_nGnRnE	0