rhel: Add case for RHEL 7.5 major version to kmod manage script

A Centos 7.5 kernel with an unencountered set of minor build numbers
caused an upgrade bug.  Adding the case for the rhel 7.5 kmod management
script fixes the problem.

Signed-off-by: Greg Rose <gvrose8192@gmail.com>
Reviewed-by: Yifeng Sun <pkusunyifeng@gmail.com>
Signed-off-by: Gurucharan Shetty <guru@ovn.org>

rhel/usr_share_openvswitch_scripts_ovs-kmod-manage.sh

@@ -85,6 +85,11 @@ if [ "$mainline_major" = "3" ] && [ "$mainline_minor" = "10" ]; then
         comp_ver=11
         ver_offset=4
         installed_ver="$minor_rev"
+    elif [ "$major_rev" = "862" ]; then
+#        echo "rhel75"
+        comp_ver=11
+        ver_offset=4
+        installed_ver="$minor_rev"
     elif [ "$major_rev" = "957" ]; then
 #        echo "rhel76"
         comp_ver=10