add openocd.h for top-level declarations

Create src/openocd.h to hold declarations previously made internally
by src/main.c and src/server/server.c.  This ensures all functions
are verified to be in-sync at compile time (rather than at link),
making it easier to track down bugs.

src/Makefile.am

@@ -16,6 +16,10 @@ libopenocd_la_SOURCES = \
 	hello.c \
 	openocd.c
 
+noinst_HEADERS = \
+	openocd.h
+
+
 # set the include path found by configure
 AM_CPPFLAGS = \
 	-I$(top_srcdir)/src \