Remove re-seeding FastLED random8/random16 in FX

wled00/FX.cpp

@@ -4087,6 +4087,7 @@ static const char _data_FX_MODE_PHASEDNOISE[] PROGMEM = "Phased Noise@!,!;!,!;!"
 
 
 uint16_t mode_twinkleup(void) {                 // A very short twinkle routine with fade-in and dual controls. By Andrew Tuline.
+  uint16_t prevSeed = random16_get_seed();      // save seed so we can restore it at the end of the function
   random16_set_seed(535);                       // The randomizer needs to be re-set each time through the loop in order for the same 'random' numbers to be the same each time through.
 
   for (int i = 0; i < SEGLEN; i++) {
@@ -4096,6 +4097,7 @@ uint16_t mode_twinkleup(void) {                 // A very short twinkle routine
     SEGMENT.setPixelColor(i, color_blend(SEGCOLOR(1), SEGMENT.color_from_palette(random8()+strip.now/100, false, PALETTE_SOLID_WRAP, 0), pixBri));
   }
 
+  random16_set_seed(prevSeed); // restore original seed so other effects can use "random" PRNG
   return FRAMETIME;
 }
 static const char _data_FX_MODE_TWINKLEUP[] PROGMEM = "Twinkleup@!,Intensity;!,!;!;;m12=0";