bpmp: Reduce freq to 589MHz

3 users had issues with 602MHz.
This will probably bring the SoC binning compatibility to 100%.

Additionally, make it easy to change default boost frequency.

The tiny loss in perf, will be mitigated in Nyx. (It's actually even faster)

bootloader/main.c

@@ -1282,7 +1282,7 @@ void ipl_main()
 	//display_backlight_brightness(h_cfg.backlight, 1000);
 
 	// Overclock BPMP.
-	bpmp_clk_rate_set(BPMP_CLK_SUPER_BOOST);
+	bpmp_clk_rate_set(BPMP_CLK_DEFAULT_BOOST);
 
 	// Check if we had a panic while in CFW.
 	secmon_exo_check_panic();