tirpc: use pkg-config to find details

Hardcoding paths breaks cross-compiling, so use the pkg-config files
that libtirpc already provides.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

configure.ac

@@ -11,6 +11,7 @@ AC_PROG_CC
 AC_PROG_LIBTOOL
 
 AM_PROG_CC_C_O
+PKG_PROG_PKG_CONFIG
 
 # Work around stupid autoconf default cflags. pt 2
 if test "$SAVE_CFLAGS" = "x"; then
@@ -71,12 +72,18 @@ AC_CHECK_MEMBER([struct sockaddr.sa_len],
 #include <sys/socket.h>
 ])
 
-echo "Use TI-RPC: $enable_tirpc"
+LIBNFS_PC_REQ_PRIVATE=
+
 if test "$enable_tirpc" = "yes"; then
-	CFLAGS="${CFLAGS} -I /usr/include/tirpc"
-	LDFLAGS="${LDFLAGS} -ltirpc"
+	PKG_CHECK_MODULES(TIRPC, libtirpc, [],
+		AC_MSG_ERROR([unable to locate libtirpc files]))
+	CFLAGS="${CFLAGS} ${TIRPC_CFLAGS}"
+	LIBS="${LIBS} ${TIRPC_LIBS}"
+	LIBNFS_PC_REQ_PRIVATE="${LIBNFS_PC_REQ_PRIVATE} libtirpc"
 fi
 
+AC_SUBST(LIBNFS_PC_REQ_PRIVATE)
+
 #output
 AC_CONFIG_FILES([Makefile]
                 [include/Makefile]

libnfs.pc.in

@@ -12,3 +12,4 @@ Requires:
 Conflicts:
 Libs: -L${libdir} -lnfs
 Cflags: -I${includedir}
+Requires.private: @LIBNFS_PC_REQ_PRIVATE@