[cmdline] Convert aws_get_boot_creds_from_secret and userdata commands to COMMAND macro

Convert aws_get_boot_creds_from_secret and userdata commands from the legacy struct command format to use the new COMMAND() macro.

Author: Eric Chehata

src/hci/commands/aws_get_boot_creds_from_secret_cmd.c

@@ -291,7 +291,4 @@ static int aws_get_boot_creds_from_secret_exec ( int argc, char **argv ) {
 }
 
 /** AWS get boot credentials from secret command */
-struct command aws_get_boot_creds_from_secret __command = {
-	.name = "aws_get_boot_creds_from_secret",
-	.exec = aws_get_boot_creds_from_secret_exec,
-};
+COMMAND ( aws_get_boot_creds_from_secret, aws_get_boot_creds_from_secret_exec );

src/hci/commands/userdata_cmd.c

@@ -85,7 +85,4 @@ static int userdata_exec ( int argc, char **argv ) {
 }
 
 /** userdata command */
-struct command userdata_command __command = {
-	.name = "userdata",
-	.exec = userdata_exec,
-};
+COMMAND ( userdata, userdata_exec );