ARM: Add final piece to fix XIP decompressor in read-only memory

This defines STATIC_RW_DATA, which prevents the read/write malloc
management data being declared with a static attribute.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/boot/compressed/decompress.c

@@ -11,6 +11,7 @@ extern unsigned long free_mem_end_ptr;
 extern void error(char *);
 
 #define STATIC static
+#define STATIC_RW_DATA	/* non-static please */
 
 #define ARCH_HAS_DECOMP_WDOG