Use "uname -m" for architecture

On RHEL10 in some circumstances (podman, x86_64), "uname -i" returns
"unknown", but "uname -m" returns "x86_64". This needs more thorough
checking for other architectures of concern.

Signed-off-by: Jonathan Dowland <[email protected]>

Author: jmtd

modules/jdk/21/configure.sh

@@ -14,7 +14,7 @@ cp -pr * /
 popd
 
 # Set this JDK as the alternative in use
-_arch="$(uname -i)"
+_arch="$(uname -m)"
 alternatives --set java java-21-openjdk.${_arch}
 alternatives --set javac java-21-openjdk.${_arch}
 alternatives --set java_sdk_openjdk java-21-openjdk.${_arch}