stm32f4: use new rcc_clock_setup_pll()

Batch replaced to use new api.  User code doesn't need this, but
examples should be up to date, and this avoids deprecation warnings.

examples/stm32/f4/stm32f429i-discovery/mandelbrot-lcd/clock.c

@@ -32,7 +32,7 @@
 
 void clock_setup(void)
 {
-	rcc_clock_setup_hse_3v3(&rcc_hse_8mhz_3v3[RCC_CLOCK_3V3_168MHZ]);
+	rcc_clock_setup_pll(&rcc_hse_8mhz_3v3[RCC_CLOCK_3V3_168MHZ]);
 
 	/* set up the SysTick function (1mS interrupts) */
 	systick_set_clocksource(STK_CSR_CLKSOURCE_AHB);