Removed a bogus setting for freeBSD that was pointed out by Brad

Smith and which had escaped my attention.  The commit from 8/3/2019
fixed an obvious fatal error but just replaced it with something
syntactically clean but nonsensical.  This commit just removes the
questionable line altogether.

scripts/configure

@@ -8042,7 +8042,6 @@ fi
       # Not available on all versions:  check for include file.
       SHLIB_CFLAGS="-fpic"
       LDDL_FLAGS="-shared ${LIB_SPECS}"
-      CFLAGS="${CFLAGS} -L/usr/X11R6/include"
       ;;
 
     *-netbsd*|*-openbsd*)

scripts/configure.in

@@ -1625,7 +1625,6 @@ if test $usingTcl ; then
       # Not available on all versions:  check for include file.
       SHLIB_CFLAGS="-fpic"
       LDDL_FLAGS="-shared ${LIB_SPECS}"
-      CFLAGS="${CFLAGS} -L/usr/X11R6/include"
       ;;
       
     *-netbsd*|*-openbsd*)