refactor: unroll curses submodule function generator macros.

* ext/posix/curses.c: Unroll obfuscating function generating
macros.
(LC_NUMBER, LC_NUMBER2, LC_STRING, LC_STRING2, LC_BOOL)
(LC_BOOLOK, LCW_BOOLOK, LCW_BOOLOK2, LCW_WIN2, LCW_WIN2YX)
(LC_ATTROK, LC_TOGGLEOK, LCW_WINBOOLOK, LCW_WININTOK): Remove.
* ext/include/_helpers.c (pushboolresult, pushintresult)
(pushstringresult): New macros to simplify returning a single
object on the stack.
* ext/include/curses.c (pushokresult): Likewise.
* ext/posix/ctype.c, ext/posix/curses.c, ext/posix/dirent.c,
ext/posix/fnmatch.c, ext/posix/signal.c, ext/posix/stdio.c,
ext/posix/stdlib.c, ext/posix/sys/socket.c, ext/posix/time.c,
ext/posix/unistd.c: Simplify accordingly.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>