dm: pmic: add pmic command

This is new command for the PMIC devices based on driver model PMIC API.
Command features are unchanged:
- list UCLASS pmic devices
- show or [set] operating pmic device (NEW)
- dump registers
- read byte of register at address
- write byte to register at address

The only one change for this command is 'dev' subcommand.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/common/Makefile b/common/Makefile
index 9084c73..425658c 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -211,6 +211,9 @@
 obj-$(CONFIG_USB_KEYBOARD) += usb_kbd.o
 obj-$(CONFIG_CMD_DFU) += cmd_dfu.o
 obj-$(CONFIG_CMD_GPT) += cmd_gpt.o
+
+# Power
+obj-$(CONFIG_CMD_PMIC) += cmd_pmic.o
 endif
 
 ifdef CONFIG_SPL_BUILD