toolchain-shar-relocate.sh: Add check for missing command 'file'

On a machine without the file command, the SDK install fails with a
cryptic error message.

```
xargs: file: No such file or directory
sed: no input files
Failed to replace perl. Relocate script failed. Abort!
```

Add a test for 'file' to print a clear error message.

```
The command 'file' is required by the relocation script, please install it first. Abort!
```

(From OE-Core rev: 1aa19b9e34ebe6f39a25364073fed4c069f650e8)

Signed-off-by: Tom Hochstein <tom.hochstein@nxp.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/files/toolchain-shar-relocate.sh

@@ -1,7 +1,9 @@
-if ! xargs --version > /dev/null 2>&1; then
-	echo "xargs is required by the relocation script, please install it first. Abort!"
-	exit 1
-fi
+for cmd in xargs file; do
+	if ! command -v $cmd > /dev/null 2>&1; then
+		echo "The command '$cmd' is required by the relocation script, please install it first. Abort!"
+		exit 1
+	fi
+done
 
 # fix dynamic loader paths in all ELF SDK binaries
 # allow symlinks to be accessed via the find command too