imx: imx8mm-beacon: Move environment definition to env file

Instead of cluttering up a header file with a bunch of defines,
move the default environmental variables to a file called
imx8mm_beacon.env and reference it from the defconfig.

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/board/beacon/imx8mm/imx8mm_beacon.env b/board/beacon/imx8mm/imx8mm_beacon.env
new file mode 100644
index 0000000..00bf67e
--- /dev/null
+++ b/board/beacon/imx8mm/imx8mm_beacon.env
@@ -0,0 +1,19 @@
+boot_fit=try
+bootscript=echo Running bootscript from mmc ...; source
+console=ttymxc1
+fdt_addr=0x45000000
+fdt_file=imx8mm-beacon-kit.dtb
+finduuid=part uuid mmc ${mmcdev}:2 uuid
+image=Image
+initrd_addr=0x46000000
+loadbootscript=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${script};
+loadfdt=fatload mmc ${mmcdev}:${mmcpart} ${fdt_addr} ${fdt_file}
+loadimage=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${image}
+mmcargs=setenv bootargs console=${console},${baudrate} root=PARTUUID=${uuid} rootwait rw ${mtdparts} ${optargs}
+mmcautodetect=yes
+mmcboot=echo Booting from mmc ...; run finduuid; run mmcargs; if run loadfdt; then booti ${loadaddr} - ${fdt_addr}; else echo WARN: Cannot load the DT; fi;
+netargs=setenv bootargs console=${console},${baudrate} root=/dev/nfs ip=dhcp nfsroot=${serverip}:${nfsroot},v3,tcp
+mmcdev=1
+mmcpart=1
+netboot=echo Booting from net ...; run netargs;  if test ${ip_dyn} = yes; then setenv get_cmd dhcp; else setenv get_cmd tftp; fi; ${get_cmd} ${loadaddr} ${image}; if test ${boot_fit} = yes || test ${boot_fit} = try; then bootm ${loadaddr}; else if ${get_cmd} ${fdt_addr} ${fdt_file}; then booti ${loadaddr} - ${fdt_addr}; else echo WARN: Cannot load the DT; fi; fi;
+script=boot.scr