um: use %lx format specifiers for unsigned longs

static analysis from cppcheck detected %x being used for
unsigned longs:

[arch/x86/um/os-Linux/task_size.c:112]: (warning) %x in format
  string (no. 1) requires 'unsigned int' but the argument type
  is 'unsigned long'.

Use %lx instead of %x

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/x86/um/os-Linux/task_size.c

@@ -109,7 +109,7 @@ unsigned long os_get_top_address(void)
 		exit(1);
 	}
 
-	printf("0x%x\n", bottom << UM_KERN_PAGE_SHIFT);
+	printf("0x%lx\n", bottom << UM_KERN_PAGE_SHIFT);
 	printf("Locating the top of the address space ... ");
 	fflush(stdout);
 
@@ -134,7 +134,7 @@ out:
 		exit(1);
 	}
 	top <<= UM_KERN_PAGE_SHIFT;
-	printf("0x%x\n", top);
+	printf("0x%lx\n", top);
 
 	return top;
 }