ovs-dev.py: Only build the Linux datapath with GCC.

In practice, Linux kernel modules are only built with GCC, so it
doesn't make much sense to spend time compiling them with clang.

Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Joe Stringer <joestringer@nicira.com>

utilities/ovs-dev.py

@@ -62,7 +62,6 @@ def conf():
 
     configure = ["../configure", "--prefix=" + ROOT, "--localstatedir=" + ROOT,
                  "--with-logdir=%s/log" % ROOT, "--with-rundir=%s/run" % ROOT,
-                 "--with-linux=/lib/modules/%s/build" % uname(),
                  "--enable-silent-rules", "--with-dbdir=" + ROOT, "--silent"]
 
     if options.werror:
@@ -86,7 +85,7 @@ def conf():
         pass # Directory exists.
 
     os.chdir(BUILD_GCC)
-    _sh(*configure)
+    _sh(*(configure + ["--with-linux=/lib/modules/%s/build" % uname()]))
 
     try:
         _sh("clang --version", check=True)