code cleanup: static current_phoneme_table

src/libespeak-ng/phoneme.h

 // Several phoneme tables may be loaded into memory. phoneme_tab points to
 // one for the current voice
 extern int n_phoneme_tab;
-extern int current_phoneme_table;
 extern PHONEME_TAB *phoneme_tab[N_PHONEME_TAB];
 
 typedef struct {

src/libespeak-ng/synthdata.c

 
 // copy the current phoneme table into here
 int n_phoneme_tab;
-int current_phoneme_table;
+static int current_phoneme_table;
 PHONEME_TAB *phoneme_tab[N_PHONEME_TAB];
 
 static unsigned short *phoneme_index = NULL;
 	phoneme_index = NULL;
 	phondata_ptr = NULL;
 	tunes = NULL;
+	current_phoneme_table = -1;
 }
 
 int PhonemeCode(unsigned int mnem)
 
 void SelectPhonemeTable(int number)
 {
+	if (current_phoneme_table == number) return;
 	n_phoneme_tab = 0;
 	MAKE_MEM_UNDEFINED(&phoneme_tab, sizeof(phoneme_tab));
 	SetUpPhonemeTable(number); // recursively for included phoneme tables

src/libespeak-ng/synthesize.c

 		return 0;
 	}
 
-	if (current_phoneme_table != voice->phoneme_tab_ix)
-		SelectPhonemeTable(voice->phoneme_tab_ix);
+	SelectPhonemeTable(voice->phoneme_tab_ix);
 
 	// read the next clause from the input text file, translate it, and generate
 	// entries in the wavegen command queue