Consolidate API of target_supports_multi_process

This simple commit consolidates the API of
target_supports_multi_process.  Since both GDB and gdbserver use the
same function prototype, all that was needed was to move create this
prototype on gdb/target/target.h and turn the macros declared on
gdb/{,gdbserver/}target.h into actual functions.

Regtested (clean pass) on the BuildBot.

gdb/ChangeLog:
2016-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>

	* target.c (target_supports_multi_process): New function, moved
	from...
	* target.h (target_supports_multi_process): ... here.  Remove
	macro.
	* target/target.h (target_supports_multi_process): New prototype.

gdb/gdbserver/ChangeLog:
2016-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>

	* target.c (target_supports_multi_process): New function, moved
	from...
	* target.h (target_supports_multi_process): ... here.  Remove
	macro.

gdb/ChangeLog

@@ -1,3 +1,11 @@
+2016-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>
+
+	* target.c (target_supports_multi_process): New function, moved
+	from...
+	* target.h (target_supports_multi_process): ... here.  Remove
+	macro.
+	* target/target.h (target_supports_multi_process): New prototype.
+
 2016-10-06  Pedro Alves  <palves@redhat.com>
 
 	* cp-valprint.c (vtbl_ptr_name): Write "extern const" instead of

gdb/gdbserver/ChangeLog

@@ -1,3 +1,10 @@
+2016-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>
+
+	* target.c (target_supports_multi_process): New function, moved
+	from...
+	* target.h (target_supports_multi_process): ... here.  Remove
+	macro.
+
 2016-10-05  Tom Tromey  <tom@tromey.com>
 
 	PR remote/20655:

gdb/gdbserver/target.c

@@ -302,6 +302,15 @@ target_continue (ptid_t ptid, enum gdb_signal signal)
   (*the_target->resume) (&resume_info, 1);
 }
 
+/* See target/target.h.  */
+
+int
+target_supports_multi_process (void)
+{
+  return (the_target->supports_multi_process != NULL ?
+	  (*the_target->supports_multi_process) () : 0);
+}
+
 int
 start_non_stop (int nonstop)
 {

gdb/gdbserver/target.h

@@ -535,10 +535,6 @@ int kill_inferior (int);
 #define target_async(enable) \
   (the_target->async ? (*the_target->async) (enable) : 0)
 
-#define target_supports_multi_process() \
-  (the_target->supports_multi_process ? \
-   (*the_target->supports_multi_process) () : 0)
-
 #define target_process_qsupported(features, count)	\
   do							\
     {							\

gdb/target.c

@@ -2727,6 +2727,14 @@ target_supports_disable_randomization (void)
   return 0;
 }
 
+/* See target/target.h.  */
+
+int
+target_supports_multi_process (void)
+{
+  return (*current_target.to_supports_multi_process) (&current_target);
+}
+
 char *
 target_get_osdata (const char *type)
 {

gdb/target.h

@@ -1380,12 +1380,6 @@ struct address_space *target_thread_address_space (ptid_t);
 
 int target_info_proc (const char *, enum info_proc_what);
 
-/* Returns true if this target can debug multiple processes
-   simultaneously.  */
-
-#define	target_supports_multi_process()	\
-     (*current_target.to_supports_multi_process) (&current_target)
-
 /* Returns true if this target can disable address space randomization.  */
 
 int target_supports_disable_randomization (void);

gdb/target/target.h

@@ -90,4 +90,9 @@ extern ptid_t target_wait (ptid_t ptid, struct target_waitstatus *status,
 
 extern void target_mourn_inferior (ptid_t ptid);
 
+/* Return 1 if this target can debug multiple processes
+   simultaneously, zero otherwise.  */
+
+extern int target_supports_multi_process (void);
+
 #endif /* TARGET_COMMON_H */