Make TkCygwinMainEx() work when Tk 8.7 is compiled against Tcl 9.0 (c… #376

Job	Run time
test (gcc)	3m 51s
build (gcc)	1m 42s
test (gcc, --disable-xft)	3m 49s
test (gcc, --enable-symbols)	3m 19s
build (gcc, CFLAGS=-DTK_NO_DEPRECATED=1)	1m 39s
build (gcc, --disable-xft)	2m 4s
build (gcc, --disable-xss)	1m 42s
build (gcc, --enable-symbols)	1m 21s
build (clang)	1m 59s
build (clang, CFLAGS=-DTK_NO_DEPRECATED=1)	2m 10s
build (clang, --disable-xft)	1m 51s
build (clang, --disable-xss)	1m 55s
build (clang, --enable-symbols)	1m 27s
	28m 49s

Provide feedback