log: remove func loc info unless MM_LOG_FUNC_LOC is defined

The user can build the project passing custom CFLAGS to enable the
function location information, e.g.:

    $ ./configure --prefix=/usr CFLAGS="-DMM_LOG_FUNC_LOC"

src/main.c

@@ -143,7 +143,6 @@ main (int argc, char *argv[])
                        mm_context_get_log_file (),
                        mm_context_get_log_timestamps (),
                        mm_context_get_log_relative_timestamps (),
-                       mm_context_get_debug (),
                        &err)) {
         g_warning ("Failed to set up logging: %s", err->message);
         g_error_free (err);

src/mm-log.c

@@ -47,7 +47,6 @@ static gboolean ts_flags = TS_FLAG_NONE;
 static guint32 log_level = LOGL_INFO | LOGL_WARN | LOGL_ERR;
 static GTimeVal rel_start = { 0, 0 };
 static int logfd = -1;
-static gboolean func_loc = FALSE;
 
 typedef struct {
     guint32 num;
@@ -117,8 +116,9 @@ _mm_log (const char *loc,
         g_string_append_printf (msgbuf, "[%06ld.%06ld] ", secs, usecs);
     }
 
-    if (func_loc && log_level & LOGL_DEBUG)
-        g_string_append_printf (msgbuf, "[%s] %s(): ", loc, func);
+#if defined MM_LOG_FUNC_LOC
+    g_string_append_printf (msgbuf, "[%s] %s(): ", loc, func);
+#endif
 
     va_start (args, fmt);
     g_string_append_vprintf (msgbuf, fmt, args);
@@ -209,15 +209,12 @@ mm_log_setup (const char *level,
               const char *log_file,
               gboolean show_timestamps,
               gboolean rel_timestamps,
-              gboolean debug_func_loc,
               GError **error)
 {
     /* levels */
     if (level && strlen (level) && !mm_log_set_level (level, error))
         return FALSE;
 
-    func_loc = debug_func_loc;
-
     if (show_timestamps)
         ts_flags = TS_FLAG_WALL;
     else if (rel_timestamps)

src/mm-log.h

@@ -53,7 +53,6 @@ gboolean mm_log_setup (const char *level,
                        const char *log_file,
                        gboolean show_ts,
                        gboolean rel_ts,
-                       gboolean debug_func_loc,
                        GError **error);
 
 void mm_log_shutdown (void);