clk: meson-gxbb: Add GXL/GXM GP0 Variant

The clock tree in the Amlogic GXBB and GXL/GXM SoCs is shared, but the GXL/GXM
SoCs embeds a different GP0 PLL, and needs different parameters with a vendor
provided reduced rate table.

This patch adds the GXL GP0 variant, and adds a GXL DT compatible in order
to use the GXL GP0 PLL instead of the GXBB specific one.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/1490178747-14837-4-git-send-email-narmstrong@baylibre.com

drivers/clk/meson/gxbb.h

@@ -71,6 +71,8 @@
 #define HHI_GP0_PLL_CNTL2		0x44 /* 0x11 offset in data sheet */
 #define HHI_GP0_PLL_CNTL3		0x48 /* 0x12 offset in data sheet */
 #define HHI_GP0_PLL_CNTL4		0x4c /* 0x13 offset in data sheet */
+#define	HHI_GP0_PLL_CNTL5		0x50 /* 0x14 offset in data sheet */
+#define	HHI_GP0_PLL_CNTL1		0x58 /* 0x16 offset in data sheet */
 
 #define HHI_XTAL_DIVN_CNTL		0xbc /* 0x2f offset in data sheet */
 #define HHI_TIMER90K			0xec /* 0x3b offset in data sheet */