(ITS#8830) build hardcodes gcc

[vcunat]

Full_Name: Vladim.r Čun.t
Version: 0.9.22 (lmdb)
OS: Linux (NixOS)
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (178.255.168.34)


Some parts of the LMDB Makefile hardcode gcc, seemingly unnecessarily.  Please
apply the following patch or some similar fix.

commit 029031a68873bc3784a8561bd8e049efbd34f9d0 (HEAD)
Author: Vladimír &#268;unát <vcu...@gmail.com>
Date:   Sun Apr 1 11:05:31 2018 +0200

    make: gcc -> $(CC)

diff --git a/libraries/liblmdb/Makefile b/libraries/liblmdb/Makefile
index f254511..612484e 100644
--- a/libraries/liblmdb/Makefile
+++ b/libraries/liblmdb/Makefile
@@ -102,13 +102,13 @@ COV_OBJS=xmdb.o xmidl.o
 
 coverage: xmtest
        for i in mtest*.c [0-9]*.c; do j=`basename \$$i .c`; $(MAKE) $$j.o; \
-               gcc -o x$$j $$j.o $(COV_OBJS) -pthread $(COV_FLAGS); \
+               $(CC) -o x$$j $$j.o $(COV_OBJS) -pthread $(COV_FLAGS); \
                rm -rf testdb; mkdir testdb; ./x$$j; done
        gcov xmdb.c
        gcov xmidl.c
 
 xmtest:        mtest.o xmdb.o xmidl.o
-       gcc -o xmtest mtest.o xmdb.o xmidl.o -pthread $(COV_FLAGS)
+       $(CC) -o xmtest mtest.o xmdb.o xmidl.o -pthread $(COV_FLAGS)
 
 xmdb.o: mdb.c lmdb.h midl.h
        $(CC) $(CFLAGS) -fPIC $(CPPFLAGS) -O0 $(COV_FLAGS) -c mdb.c -o $@