check_type: remove gratuitous trailing whitespace.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

ccan/check_type/check_type.h

@@ -38,7 +38,7 @@
  *
  * Example:
  *	// Do subtraction to get to enclosing type, but make sure that
- *	// pointer is of correct type for that member. 
+ *	// pointer is of correct type for that member.
  *	#define container_of(mbr_ptr, encl_type, mbr)			\
  *		(check_types_match((mbr_ptr), &((encl_type *)0)->mbr),	\
  *		 ((encl_type *)						\