Revert "obs-ffmpeg/nvenc: Remove "default" preset"

This reverts commit d1343dc064484aacaf3e34e477111795b555b758.

Apparently people are having issues caused by this specific commit.
Going to temporarily revert for the time being.

plugins/obs-ffmpeg/obs-ffmpeg-nvenc.c

@@ -158,10 +158,6 @@ static bool nvenc_update(void *data, obs_data_t *settings)
 		rc = "CBR";
 	}
 
-	/* The "default" preset has been deprecated */
-	if (preset && astrcmpi(preset, "default") == 0)
-		preset = "hq";
-
 	info.format = voi->format;
 	info.colorspace = voi->colorspace;
 	info.range = voi->range;
@@ -388,7 +384,7 @@ static void nvenc_defaults(obs_data_t *settings)
 	obs_data_set_default_int(settings, "keyint_sec", 0);
 	obs_data_set_default_int(settings, "cqp", 23);
 	obs_data_set_default_string(settings, "rate_control", "CBR");
-	obs_data_set_default_string(settings, "preset", "hq");
+	obs_data_set_default_string(settings, "preset", "default");
 	obs_data_set_default_string(settings, "profile", "main");
 	obs_data_set_default_string(settings, "level", "auto");
 	obs_data_set_default_bool(settings, "2pass", true);
@@ -452,6 +448,7 @@ static obs_properties_t *nvenc_properties(void *unused)
 #define add_preset(val) \
 	obs_property_list_add_string(p, obs_module_text("NVENC.Preset." val), \
 			val)
+	add_preset("default");
 	add_preset("hq");
 	add_preset("hp");
 	add_preset("bd");