make install support common/ and tests/ dirs (V4)
  * reposted for current top of tree changes. [rjohnston@sgi.com]
  * use the neater way by Dave to get the TESTS_SUBDIRS in tests/Makefile.
Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
[rjohnston@sgi.com Reposted for current top of tree changes]
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Rich Johnston <rjohnston@sgi.com>
 TOPDIR = ..
 include $(TOPDIR)/include/builddefs
 
-TESTS_SUBDIRS = $(shell find . -maxdepth 1 -type d | sed -n -e 's/\.\///gp')
+TESTS_SUBDIRS = $(sort $(dir $(wildcard $(PWD)/$(TESTS_DIR)/[a-z]*/)))
 
 include $(BUILDRULES)