Add manylinux_2_28-aarch64 image and fix qemu path in 2_34 variant

Add a new manylinux_2_28-aarch64 cross-compilation image targeting
AlmaLinux 8 (glibc 2.28) for building portable Python wheels for
aarch64 from x86_64 hosts. Based on the manylinux_2_34-aarch64
variant with adjusted glibc (2.28) and kernel headers (4.18).

Also fix CMAKE_CROSSCOMPILING_EMULATOR in the 2_34 Toolchain.cmake
to use /usr/bin/qemu-aarch64-static (matching what the Dockerfile
actually installs).

manylinux_2_28-aarch64/xc_script/repair_wheel.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# AUTHOR:      odidev
+# DATE:        2021-07-20
+# DESCRIPTION: The wheels are cross compiled and we can't be repair in currnet
+#              environment. So, better to repair in manylinux container. So,
+#              we need to run BEFORE_ALL again in target manylinux contaner. So,
+#              instead of running BEFORE_ALL again we can copy the stored files.
+# INPUT:       $1 --> Dependeicies install path on host machine with respect to
+#                     container
+#              $2 --> Wheel repair command
+
+install_dir="$1"
+
+for file in `find $install_dir -type f`; do
+    install_path=$(echo ${file} | sed 's/^.*usr/\/usr/')
+    install -m 0644 -D ${file} ${install_path}
+done
+
+$2