phycore_imx8mm: Switch to using env text files

Move the environment into the board directory and convert header to a
txt file. In addition, this patch also applies following changes:

- Change default nfsroot path to /srv/nfs due to compliance with Linux
FHS 3.0.

- Rename specific variables as stated in the bootstd documentation.
Renamed variables:
	fdt_addr => fdt_addr_r
	fdt_file => fdtfile

Signed-off-by: Yunus Bas <y.bas@phytec.de>

include/configs/phycore_imx8mm.h

@@ -20,52 +20,6 @@
 /* For RAW image gives a error info not panic */
 #endif
 
-#define CFG_EXTRA_ENV_SETTINGS \
-	"image=Image\0" \
-	"console=ttymxc2,115200\0" \
-	"fdt_addr=0x48000000\0" \
-	"fdt_file=" CONFIG_DEFAULT_FDT_FILE "\0" \
-	"ip_dyn=yes\0" \
-	"mmcdev=" __stringify(CONFIG_SYS_MMC_ENV_DEV) "\0" \
-	"mmcpart=1\0" \
-	"mmcroot=2\0" \
-	"update_offset=0x42\0" \
-	"update_filename=flash.bin\0" \
-	"update_bootimg="						\
-		"mmc dev ${mmcdev} ; "		\
-		"if dhcp ${loadaddr} ${update_filepath}/${update_filename} ; then "	\
-		"setexpr fw_sz ${filesize} / 0x200 ; "	/* SD block size */ \
-		"mmc write ${loadaddr} ${update_offset} ${fw_sz} ; "	\
-		"fi\0" \
-	"mmcautodetect=yes\0" \
-	"mmcargs=setenv bootargs console=${console} " \
-		"root=/dev/mmcblk${mmcdev}p${mmcroot} rootwait rw\0" \
-	"loadimage=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${image}\0" \
-	"loadfdt=fatload mmc ${mmcdev}:${mmcpart} ${fdt_addr} ${fdt_file}\0" \
-	"mmcboot=echo Booting from mmc ...; " \
-		"run mmcargs; " \
-		"if run loadfdt; then " \
-			"booti ${loadaddr} - ${fdt_addr}; " \
-		"else " \
-			"echo WARN: Cannot load the DT; " \
-		"fi;\0 " \
-	"nfsroot=/nfs\0" \
-	"netargs=setenv bootargs console=${console} root=/dev/nfs ip=dhcp " \
-		"nfsroot=${serverip}:${nfsroot},v3,tcp\0" \
-	"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 ${get_cmd} ${fdt_addr} ${fdt_file}; then " \
-			"booti ${loadaddr} - ${fdt_addr}; " \
-		"else " \
-			"echo WARN: Cannot load the DT; " \
-		"fi;\0" \
-
 /* Link Definitions */
 
 #define CFG_SYS_INIT_RAM_ADDR	0x40000000