src/include: Fix unsigned warnings

Fix warning detected by checkpatch.pl:

WARNING: Prefer 'unsigned int' to bare use of 'unsigned'

BRANCH=none
BUG=None
TEST=Build and run on Galileo Gen2

Change-Id: I23d9b4b715aa74acc387db8fb8d3c73bd5cabfaa
Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com>
Reviewed-on: https://review.coreboot.org/18607
Reviewed-by: Philippe Mathieu-Daudé <philippe.mathieu.daude@gmail.com>
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>

src/include/delay.h

@@ -3,7 +3,7 @@
 
 void init_timer(void);
 
-void udelay(unsigned usecs);
-void mdelay(unsigned msecs);
-void delay(unsigned secs);
+void udelay(unsigned int usecs);
+void mdelay(unsigned int msecs);
+void delay(unsigned int secs);
 #endif /* DELAY_H */