Support up to 300 voices/languages to make some space

src/libespeak-ng/voices.c

@@ -62,7 +62,7 @@ static int formant_rate_22050[9] = { 240, 170, 170, 170, 170, 170, 170, 170, 170
 int formant_rate[9]; // values adjusted for actual sample rate
 
 #define DEFAULT_LANGUAGE_PRIORITY  5
-#define N_VOICES_LIST  275
+#define N_VOICES_LIST  300
 static int n_voices_list = 0;
 static espeak_VOICE *voices_list[N_VOICES_LIST];