clk: lpc32xx: add HCLK PLL output configuration

This patch add the support to setup the HCLK PLL output
using the "assigned-clock-rates" parameter in the device tree.

If the option is not use, the clock setup by the kickstart
and/or bootloader remain unchanged.

The previous kernel version did not change the clock frequency
output setup by the kickstart and/or bootloader;
this version always setup the clock frequency output to 208MHz.

Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

include/dt-bindings/clock/lpc32xx-clock.h

@@ -47,6 +47,7 @@
 #define LPC32XX_CLK_PWM1	32
 #define LPC32XX_CLK_PWM2	33
 #define LPC32XX_CLK_ADC		34
+#define LPC32XX_CLK_HCLK_PLL	35
 
 /* LPC32XX USB clocks */
 #define LPC32XX_USB_CLK_I2C	1