Eliminate use of BUILD_tk in tkListbox.c #519

Job	Run time
test (gcc)	4m 25s
build (gcc)	1m 39s
test (gcc, --disable-xft)	4m 6s
build (gcc, CFLAGS=-DTK_NO_DEPRECATED=1)	1m 51s
test (gcc, --enable-symbols)	3m 30s
build (gcc, --disable-shared)	1m 36s
build (gcc, --disable-xft)	1m 38s
build (gcc, --disable-xss)	1m 38s
build (gcc, --enable-symbols)	1m 11s
build (clang)	2m 4s
build (clang, CFLAGS=-DTK_NO_DEPRECATED=1)	2m 11s
build (clang, --disable-shared)	1m 58s
build (clang, --disable-xft)	1m 47s
build (clang, --disable-xss)	1m 48s
build (clang, --enable-symbols)	1m 22s
	32m 44s

Provide feedback