Remove unused conditional tests.

src/libespeak-ng/compiledata.c

 	{ "isSibilant", 0, i_isSibilant },
 	{ "isFlag1",    0, i_isFlag1 },
 	{ "isFlag2",    0, i_isFlag2 },
-	{ "isFlag3",    0, i_isFlag3 },
 
 	{ "isVel", 0, i_isVel },
 
 	{ "isStressed",    0, i_isStressed },
 	{ "isMaxStress",   0, i_isMaxStress },
 
-	{ "isBreak",            0, i_isBreak },
-	{ "isPause2",           0, i_isBreak },  // synonym for isBreak
+	{ "isPause2",           0, i_isBreak },
 	{ "isWordStart",        0, i_isWordStart },
-	{ "notWordStart",       0, i_notWordStart },
 	{ "isWordEnd",          0, i_isWordEnd },
 	{ "isAfterStress",      0, i_isAfterStress },
 	{ "isNotVowel",         0, i_isNotVowel },

src/libespeak-ng/synthdata.c

 				return (ph->type == phPAUSE) || (plist_this->synthflags & SFLAG_NEXT_PAUSE);
 			case 6: // isWordStart
 				return plist->sourceix != 0;
-			case 7: // notWordStart
-				return plist->sourceix == 0;
 			case 8: // isWordEnd
 				return plist[1].sourceix || (plist[1].ph->type == phPAUSE);
 			case 9: // isAfterStress

src/libespeak-ng/synthesize.h

 
 #define i_isBreak      0x85
 #define i_isWordStart  0x86
-#define i_notWordStart 0x87
 #define i_isWordEnd    0x88
 #define i_isAfterStress 0x89
 #define i_isNotVowel   0x8a
 #define i_isRhotic     0x57 // bit 23 in phflags
 #define i_isFlag1      0x5c
 #define i_isFlag2      0x5d
-#define i_isFlag3      0x5e
 
 #define i_StressLevel  0x800