[review] core: add VCORE_FREE_{PA,SZ,END_PA}

Update.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

core/include/kernel/linker.h

@@ -52,6 +52,7 @@ extern const uint8_t __extab_end[];
 					  __vcore_free_start))
 #define VCORE_FREE_END_PA	((unsigned long)__vcore_free_end)
 #else
+/* No VCORE_FREE range in pager configuration since it uses all memory */
 #define VCORE_FREE_PA		PADDR_MAX
 #define VCORE_FREE_SZ		0
 #define VCORE_FREE_END_PA	PADDR_MAX