imx: cleanup bootaux

Move i.MX6/7 bootaux code to imx_bootaux.c.
The i.MX6/7 has different src layout, so define M4 reg offset
to ease the cleanup. Redefine the M4 related BIT for share
common code.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
diff --git a/arch/arm/include/asm/arch-mx6/imx-regs.h b/arch/arm/include/asm/arch-mx6/imx-regs.h
index 48ce0ed..8513406 100644
--- a/arch/arm/include/asm/arch-mx6/imx-regs.h
+++ b/arch/arm/include/asm/arch-mx6/imx-regs.h
@@ -482,10 +482,11 @@
 
 #define src_base ((struct src *)SRC_BASE_ADDR)
 
-#define SRC_SCR_M4_ENABLE_OFFSET                22
-#define SRC_SCR_M4_ENABLE_MASK                  (1 << 22)
-#define SRC_SCR_M4C_NON_SCLR_RST_OFFSET         4
-#define SRC_SCR_M4C_NON_SCLR_RST_MASK           (1 << 4)
+#define SRC_M4_REG_OFFSET		0
+#define SRC_M4_ENABLE_OFFSET		22
+#define SRC_M4_ENABLE_MASK		BIT(22)
+#define SRC_M4C_NON_SCLR_RST_OFFSET	4
+#define SRC_M4C_NON_SCLR_RST_MASK	BIT(4)
 
 /* GPR1 bitfields */
 #define IOMUXC_GPR1_APP_CLK_REQ_N		BIT(30)