MEDIUM: xxhash: use the XXH_INLINE_ALL macro to inline all functions

This way we make all xxhash functions inline, with implementations being
directly included within xxhash.h.

Makefile is updated as well, since we don't need to compile and link
xxhash.o anymore.

Inlining should improve performance on small data inputs.

Makefile

@@ -847,7 +847,7 @@ OBJS += src/mux_h2.o src/mux_fcgi.o src/http_ana.o src/stream.o                \
         src/mworker-prog.o src/signal.o src/proto_udp.o src/lb_map.o           \
         src/sock_inet.o src/ev_select.o src/cfgparse-tcp.o                     \
         src/action.o src/thread.o src/sha1.o src/ebmbtree.o                    \
-        src/cfgparse-unix.o src/dict.o src/xxhash.o src/time.o                 \
+        src/cfgparse-unix.o src/dict.o src/time.o                              \
         src/hpack-dec.o src/arg.o src/hpack-tbl.o src/eb64tree.o               \
         src/chunk.o src/shctx.o src/regex.o src/fcgi.o src/eb32tree.o          \
         src/eb32sctree.o src/dynbuf.o src/pipe.o src/lru.o                     \

include/haproxy/defaults.h

@@ -388,4 +388,11 @@
 #define MAX_POLLERS	10
 #endif
 
+/* Make all xxhash functions inline, with implementations being directly
+ * included within xxhash.h.
+ */
+#ifndef XXH_INLINE_ALL
+#define XXH_INLINE_ALL
+#endif
+
 #endif /* _HAPROXY_DEFAULTS_H */

include/import/xxhash.h

@@ -75,6 +75,8 @@ XXH32        6.8 GB/s            6.0 GB/s
 extern "C" {
 #endif
 
+#include <haproxy/defaults.h>
+
 /* ****************************
  *  INLINE mode
  ******************************/