REORG: include: move mworker.h to haproxy/mworker{,-t}.h

One function prototype makes reference to struct mworker_proc which was
not defined there but in global.h instead. This definition, along with
the PROC_O_* fields were moved to mworker-t.h instead.
diff --git a/src/mworker.c b/src/mworker.c
index 4f5ade2..fda5052 100644
--- a/src/mworker.c
+++ b/src/mworker.c
@@ -20,6 +20,7 @@
 #include <haproxy/api.h>
 #include <common/cfgparse.h>
 #include <haproxy/list.h>
+#include <haproxy/mworker.h>
 #include <haproxy/version.h>
 
 #include <types/cli.h>
@@ -31,7 +32,6 @@
 #include <haproxy/fd.h>
 #include <proto/listener.h>
 #include <proto/log.h>
-#include <proto/mworker.h>
 #include <proto/proxy.h>
 #include <proto/signal.h>
 #include <proto/stream.h>