commands: parse seek time arguments like time options

This means a commands like "seek 13:00 absolute" actually behaves like
"--start=13:00", instead of interpreting the argument as fraction as
with normal float options. This is probably slightly closer to what
you'd expect.

As a consequence, the seek argument's type changes from float to double
internally.

core/command.c

@@ -1723,7 +1723,7 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
     int osdl = msg_osd ? 1 : OSD_LEVEL_INVISIBLE;
     switch (cmd->id) {
     case MP_CMD_SEEK: {
-        float v = cmd->args[0].v.f;
+        double v = cmd->args[0].v.d;
         int abs = cmd->args[1].v.i;
         int exact = cmd->args[2].v.i;
         if (abs == 2) {   // Absolute seek to a timestamp in seconds

core/input/input.c

@@ -92,6 +92,7 @@ struct key_name {
 #define ARG_STRING              { .type = {"", NULL, &m_option_type_string} }
 #define ARG_CHOICE(c)           { .type = {"", NULL, &m_option_type_choice,    \
                                            M_CHOICES(c)} }
+#define ARG_TIME                { .type = {"", NULL, &m_option_type_time} }
 
 #define OARG_FLOAT(def)         { .type = {"", NULL, &m_option_type_float},    \
                                   .optional = true, .v.f = def }
@@ -117,7 +118,7 @@ static const mp_cmd_t mp_cmds[] = {
   { MP_CMD_RADIO_STEP_FREQ, "radio_step_freq", {ARG_FLOAT } },
 
   { MP_CMD_SEEK, "seek", {
-      ARG_FLOAT,
+      ARG_TIME,
       OARG_CHOICE(0, ({"relative", 0},          {"0", 0},
                       {"absolute-percent", 1},  {"1", 1},
                       {"absolute", 2},          {"2", 2})),

core/input/input.h

@@ -121,6 +121,7 @@ struct mp_cmd_arg {
     union {
         int i;
         float f;
+        double d;
         char *s;
     } v;
 };