[ATM] ambassador,firestream: "-1 >>" is implementation defined

6.5.7(5): The result of E1 >> E2 is E1 right-shifted E2 bit positions.
		...
	If E1 has a signed type and a negative value, the resulting value
	is implementation defined.

So, cast -1 to unsigned type to make result well-defined.

[ Modified to use ~0U based upon recommendation from Al Viro. -DaveM ]

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/atm/firestream.c b/drivers/atm/firestream.c
index 697ad82..9c67df5 100644
--- a/drivers/atm/firestream.c
+++ b/drivers/atm/firestream.c
@@ -512,7 +512,7 @@
 		}
 		case ROUND_UP: {
 			/* check all bits that we are discarding */
-			if (man & (-1>>9)) {
+			if (man & (~0U>>9)) {
 				man = (man>>(32-9)) + 1;
 				if (man == (1<<9)) {
 					/* no need to check for round up outside of range */