make brace placement in public header struct definitions consistent

placing the opening brace on the same line as the struct keyword/tag
is the style I prefer and seems to be the prevailing practice in more
recent additions.

these changes were generated by the command:

find include/ arch/*/bits -name '*.h' \
-exec sed -i '/^struct [^;{]*$/{N;s/\n/ /;}' {} +

and subsequently checked by hand to ensure that the regex did not pick
up any false positives.

include/fcntl.h

@@ -21,8 +21,7 @@ extern "C" {
 
 #include <bits/fcntl.h>
 
-struct flock
-{
+struct flock {
 	short l_type;
 	short l_whence;
 	off_t l_start;