Revert "tools/vm: fix page-flags build"

This reverts commit 3ddd7003
from 3.19-stable.

Patch is not suitable for 3.19-stable (breaks "make -C tools/vm").

Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

tools/vm/Makefile

@@ -3,7 +3,7 @@
 TARGETS=page-types slabinfo page_owner_sort
 
 LIB_DIR = ../lib/api
-LIBS = $(LIB_DIR)/libapi.a
+LIBS = $(LIB_DIR)/libapikfs.a
 
 CC = $(CROSS_COMPILE)gcc
 CFLAGS = -Wall -Wextra -I../lib/