append _unused to the expression defined using unused() macro

This way if variables defined using unused() macro are actually
used then code will not compile...

- removed unused usage around one argc and one argv since those
  were used

- changed one unused (char *argv[]) to unused (char **argv) to
  work with modified unused() macro definition

notmuch-client.h

@@ -53,7 +53,7 @@
 #include "talloc-extra.h"
 #include "crypto.h"
 
-#define unused(x) x __attribute__ ((unused))
+#define unused(x) x ## _unused __attribute__ ((unused))
 
 #define STRINGIFY(s) STRINGIFY_(s)
 #define STRINGIFY_(s) #s

notmuch-setup.c

@@ -121,7 +121,7 @@ parse_tag_list (void *ctx, char *response)
 
 int
 notmuch_setup_command (notmuch_config_t *config,
-		       unused (int argc), unused (char *argv[]))
+		       int argc, char *argv[])
 {
     char *response = NULL;
     size_t response_size = 0;

notmuch.c

@@ -358,7 +358,7 @@ notmuch_help_command (unused (notmuch_config_t * config), int argc, char *argv[]
  */
 static int
 notmuch_command (notmuch_config_t *config,
-		 unused(int argc), unused(char *argv[]))
+		 unused(int argc), unused(char **argv))
 {
     char *db_path;
     struct stat st;