i2c/i2c-pasemi.c: Fix unsigned return type

The function has an unsigned return type, but returns a negative constant
to indicate an error condition.  The result of calling the function is
always stored in a variable of type (signed) int, and thus unsigned can be
dropped from the return type.

A sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@exists@
identifier f;
constant C;
@@

 unsigned f(...)
 { <+...
*  return -C;
 ...+> }
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Acked-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

drivers/i2c/busses/i2c-pasemi.c

@@ -88,7 +88,7 @@ static void pasemi_smb_clear(struct pasemi_smbus *smbus)
 	reg_write(smbus, REG_SMSTA, status);
 }
 
-static unsigned int pasemi_smb_waitready(struct pasemi_smbus *smbus)
+static int pasemi_smb_waitready(struct pasemi_smbus *smbus)
 {
 	int timeout = 10;
 	unsigned int status;