drivers: clk: Add clock driver for Microchip PIC32 Microcontroller.

PIC32 clock module consists of multiple oscillators, PLLs, mutiplexers
and dividers capable of supplying clock to various controllers
on or off-chip.

Signed-off-by: Purna Chandra Mandal <purna.mandal@microchip.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

include/dt-bindings/clock/microchip,clock.h

@@ -0,0 +1,29 @@
+/*
+ * (c) 2015 Purna Chandra Mandal <purna.mandal@microchip.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ */
+
+#ifndef __CLK_MICROCHIP_PIC32
+#define __CLK_MICROCHIP_PIC32
+
+/* clock output indices */
+#define BASECLK	0
+#define PLLCLK	1
+#define MPLL	2
+#define SYSCLK	3
+#define PB1CLK	4
+#define PB2CLK	5
+#define PB3CLK	6
+#define PB4CLK	7
+#define PB5CLK	8
+#define PB6CLK	9
+#define PB7CLK	10
+#define REF1CLK	11
+#define REF2CLK	12
+#define REF3CLK	13
+#define REF4CLK	14
+#define REF5CLK	15
+
+#endif	/* __CLK_MICROCHIP_PIC32 */