Remove extraneous "mkdir -p"

The directory hierarchy is created by an mtree file (BSD.usr.dist,
in the case of calendar(1)).  An explicit "mkdir -p" in a program's
Makefile is redundant, and can mask a missing mtree entry.

usr.bin/calendar/Makefile

@@ -19,7 +19,6 @@ beforeinstall:
 	${INSTALL} -o ${BINOWN} -g ${BINGRP} -m ${TEXTMODE} \
 	    ${.CURDIR}/calendars/calendar.* ${DESTDIR}${SHAREDIR}/calendar
 .for lang in ${INTER}
-	mkdir -p ${DESTDIR}${SHAREDIR}/calendar/${lang}
 	${INSTALL} -o ${BINOWN} -g ${BINGRP} -m ${TEXTMODE} \
 		${.CURDIR}/calendars/${lang}/calendar.* \
 		${DESTDIR}${SHAREDIR}/calendar/${lang}