Fix min/max macros in include/common.h

There is a bug in the min and max macros in common.h which occurs if
Y is a larger type than X. For example, if Y is a 64-bit value and X
is a 32-bit value then Y will be truncated to 32-bits.  This fix
matches what is done in the Linux kernel but without the additional
type checking present in the kernel version.

Signed-off-by: Aaron Williams <aaron.williams@caviumnetworks.com>
diff --git a/include/common.h b/include/common.h
index 54503ed..9ba1601 100644
--- a/include/common.h
+++ b/include/common.h
@@ -180,11 +180,13 @@
  * General Purpose Utilities
  */
 #define min(X, Y)				\
-	({ typeof (X) __x = (X), __y = (Y);	\
+	({ typeof (X) __x = (X);		\
+		typeof (Y) __y = (Y);		\
 		(__x < __y) ? __x : __y; })
 
 #define max(X, Y)				\
-	({ typeof (X) __x = (X), __y = (Y);	\
+	({ typeof (X) __x = (X);		\
+		typeof (Y) __y = (Y);		\
 		(__x > __y) ? __x : __y; })
 
 #define MIN(x, y)  min(x, y)