Rename the generic "CLASS" to the more specific "GEOM_CLASS".

While I'm here remove redundancy and inconsistencies.

Obtained from: Juniper Networks

sbin/geom/Makefile.inc

@@ -1,5 +1,5 @@
 # $FreeBSD$
 
-CLASS_DIR?=/lib/geom
+GEOM_CLASS_DIR?=/lib/geom
 
 .include "../Makefile.inc"

sbin/geom/class/sched/Makefile

@@ -6,6 +6,5 @@
 GEOM_CLASS=	sched
 
 WARNS?=	6
-CLASS_DIR?=/lib/geom
 
 .include <bsd.lib.mk>

sbin/geom/core/Makefile

@@ -8,7 +8,7 @@ SRCS=	geom.c subr.c
 
 NO_SHARED=NO
 
-CFLAGS+= -DCLASS_DIR=\"${CLASS_DIR}\"
+CFLAGS+= -DGEOM_CLASS_DIR=\"${GEOM_CLASS_DIR}\"
 CFLAGS+= -I${.CURDIR}/../../../sys -I${.CURDIR} -I${.CURDIR}/..
 
 DPADD=	${LIBGEOM} ${LIBSBUF} ${LIBBSDXML} ${LIBUTIL}

sbin/geom/core/geom.c

@@ -500,7 +500,7 @@ library_path(void)
 
 	path = getenv("GEOM_LIBRARY_PATH");
 	if (path == NULL)
-		path = CLASS_DIR;
+		path = GEOM_CLASS_DIR;
 	return (path);
 }