doc: Switch from printenv to env print

The "env" command is the recommended environment management command,
its "print" subcommand is the equivalent replacement for legacy "printenv"
command. Update the documentation to use the contemporary "env print"
command instead of legacy "printenv" command.

Note that the "printenv" command is unlikely to be removed from U-Boot
in the near future due to it being integral part of the command line
ABI.

Implemented using:
$ sed -i 's@\<printenv\>@env print@g' $(git grep -li '\<printenv\>' doc/) README

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

README

@@ -754,7 +754,7 @@ The following options need to be configured:
 		directly type `$name' at the command prompt.
 
 		Global environment variables are those you use
-		env set/printenv to work with. To run a command stored
+		env set/env print to work with. To run a command stored
 		in such a variable, you need to use the run command,
 		and you must not use the '$' sign to access them.
 
@@ -1655,15 +1655,15 @@ The "bootm" command is used to boot an application that is stored in
 memory (RAM or Flash). In case of a Linux kernel image, the contents
 of the "bootargs" environment variable is passed to the kernel as
 parameters. You can check and modify this variable using the
-"printenv" and "env set" commands:
+"env print" and "env set" commands:
 
 
-	=> printenv bootargs
+	=> env print bootargs
 	bootargs=root=/dev/ram
 
 	=> env set bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
 
-	=> printenv bootargs
+	=> env print bootargs
 	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
 
 	=> bootm 40020000

doc/README.odroid

@@ -200,7 +200,7 @@ Odroid #
 Note that this automatically sets the many IP address related variables in
 U-Boot that is obtained from the DHCP server.
 
-Odroid # printenv ipaddr netmask gatewayip dnsip
+Odroid # env print ipaddr netmask gatewayip dnsip
 ipaddr=192.168.1.10
 netmask=255.255.255.0
 gatewayip=192.168.1.1
@@ -256,7 +256,7 @@ Loading: ####
 	 40 KiB/s
 done
 Bytes transferred = 46935 (b757 hex)
-Odroid # printenv bootargs
+Odroid # env print bootargs
 bootargs=Please use defined boot
 Odroid # env set bootargs console=ttySAC1,115200n8 root=/dev/mmcblk0p2 rootwait
 Odroid # bootz 40080000 - 42000000

doc/android/ab.rst

@@ -54,7 +54,7 @@ or::
 
 Result::
 
-    => printenv slot_name
+    => env print slot_name
     slot_name=a
 
 Based on this slot information, the current boot partition should be defined,

doc/usage/cmd/askenv.rst

@@ -44,7 +44,7 @@ Value of a environment variable env1 without message and size parameters:
 
     => askenv env1
     Please enter 'env1': val1
-    => printenv env1
+    => env print env1
     env1=val1
 
 Value of a environment variable env2 with message and size parameters:
@@ -53,7 +53,7 @@ Value of a environment variable env2 with message and size parameters:
 
     => askenv env2 Please type-in a value for env2: 10
     Please type-in a value for env2: 1234567890123
-    => printenv env2
+    => env print env2
     env2=1234567890
 
 Value of a environment variable env3 with size parameter only:
@@ -62,7 +62,7 @@ Value of a environment variable env3 with size parameter only:
 
     => askenv env3 10
     Please enter 'env3': val3
-    => printenv env3
+    => env print env3
     env3=val3
 
 Configuration

doc/usage/cmd/memsize.rst

@@ -34,7 +34,7 @@ This second example shows assign ram size to environment variable:
 ::
 
   => memsize memsz
-  => printenv memsz
+  => env print memsz
   memsz=8192
 
 Return value