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/sys/acct.h

@@ -14,8 +14,7 @@ extern "C" {
 
 typedef uint16_t comp_t;
 
-struct acct
-{
+struct acct {
 	char ac_flag;
 	uint16_t ac_uid;
 	uint16_t ac_gid;
@@ -36,8 +35,7 @@ struct acct
 };
 
 
-struct acct_v3
-{
+struct acct_v3 {
 	char ac_flag;
 	char ac_version;
 	uint16_t ac_tty;