[SPARC64]: Fix MAP_FIXED+shared address check, noticed by rmk.

arch/sparc64/kernel/sys_sparc.c

@@ -57,7 +57,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) && (addr & (SHMLBA - 1)))
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 			return -EINVAL;
 		return addr;
 	}