Update version to 3.7.3

Update v3.8 release notes

Fix input ndims check for regions function

Update release notes for cuDNN support and clblast upstream patch

Update package version to 3.7.1

Workaround for nvidia OpenCL if forge dependencies are missing

Bug/root-cause found by Umar while testing examples on centos container setup

Update the version for v3.6.4 (arrayfire#2505)

Set project version to 3.6.3 and add release notes

Fix FindMKL script for GNU OpenMP threading layer

(cherry picked from commit 95615a3)

Fix include dirs command in unified cmake script

(cherry picked from commit c26152f)