ARM: imx: remove Makefile.boot

Since we have converted IMX to multiplatform build, Makefile.boot is not
used anyway.  Remove it.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/mach-imx/Makefile.boot

-zreladdr-$(CONFIG_SOC_IMX1)	+= 0x08008000
-params_phys-$(CONFIG_SOC_IMX1)	:= 0x08000100
-initrd_phys-$(CONFIG_SOC_IMX1)	:= 0x08800000
-
-zreladdr-$(CONFIG_SOC_IMX21)	+= 0xC0008000
-params_phys-$(CONFIG_SOC_IMX21)	:= 0xC0000100
-initrd_phys-$(CONFIG_SOC_IMX21)	:= 0xC0800000
-
-zreladdr-$(CONFIG_SOC_IMX25)	+= 0x80008000
-params_phys-$(CONFIG_SOC_IMX25)	:= 0x80000100
-initrd_phys-$(CONFIG_SOC_IMX25)	:= 0x80800000
-
-zreladdr-$(CONFIG_SOC_IMX27)	+= 0xA0008000
-params_phys-$(CONFIG_SOC_IMX27)	:= 0xA0000100
-initrd_phys-$(CONFIG_SOC_IMX27)	:= 0xA0800000
-
-zreladdr-$(CONFIG_SOC_IMX31)	+= 0x80008000
-params_phys-$(CONFIG_SOC_IMX31)	:= 0x80000100
-initrd_phys-$(CONFIG_SOC_IMX31)	:= 0x80800000
-
-zreladdr-$(CONFIG_SOC_IMX35)	+= 0x80008000
-params_phys-$(CONFIG_SOC_IMX35)	:= 0x80000100
-initrd_phys-$(CONFIG_SOC_IMX35)	:= 0x80800000
-
-zreladdr-$(CONFIG_SOC_IMX51)	+= 0x90008000
-params_phys-$(CONFIG_SOC_IMX51)	:= 0x90000100
-initrd_phys-$(CONFIG_SOC_IMX51)	:= 0x90800000
-
-zreladdr-$(CONFIG_SOC_IMX53)	+= 0x70008000
-params_phys-$(CONFIG_SOC_IMX53)	:= 0x70000100
-initrd_phys-$(CONFIG_SOC_IMX53)	:= 0x70800000
-
-zreladdr-$(CONFIG_SOC_IMX6Q)	+= 0x10008000
-params_phys-$(CONFIG_SOC_IMX6Q)	:= 0x10000100
-initrd_phys-$(CONFIG_SOC_IMX6Q)	:= 0x10800000