MINOR: version: put the compiler version output into version.c not haproxy.c

For an unknown reason in commit bb1b63c079 I placed the compiler version
output in haproxy.c instead of version.c. Better have it in version.c which
is more suitable to this sort of things.
diff --git a/src/haproxy.c b/src/haproxy.c
index 215c68a..22c2fe5 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -3773,12 +3773,6 @@
 	deinit_and_exit(0);
 }
 
-#if defined(__clang_version__)
-REGISTER_BUILD_OPTS("Built with clang compiler version " __clang_version__);
-#elif defined(__VERSION__)
-REGISTER_BUILD_OPTS("Built with gcc compiler version " __VERSION__);
-#endif
-
 /*
  * Local variables:
  *  c-indent-level: 8
diff --git a/src/version.c b/src/version.c
index 99a8577..135ff8d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -13,3 +13,9 @@
 char haproxy_version[]      = HAPROXY_VERSION;
 char haproxy_date[]         = HAPROXY_DATE;
 char stats_version_string[] = STATS_VERSION_STRING;
+
+#if defined(__clang_version__)
+REGISTER_BUILD_OPTS("Built with clang compiler version " __clang_version__);
+#elif defined(__VERSION__)
+REGISTER_BUILD_OPTS("Built with gcc compiler version " __VERSION__);
+#endif