Remove unnecessary dkms install from base

The use of dkms in base was actually removed long ago in
Ic2c345bf9f0738dadae611194e263d3a5d424a3e and it is creating an
unnecessary dependency on EPEL for the centos elements.

Change-Id: Iae3100471e50a9c39f40b450f087192918ae54b3

elements/base/install.d/99-dkms

@@ -1,9 +0,0 @@
-#!/bin/bash
-
-if [ ${DIB_DEBUG_TRACE:-0} -gt 0 ]; then
-    set -x
-fi
-set -eu
-set -o pipefail
-
-install-packages -m base dkms_package

elements/base/pkg-map

@@ -3,14 +3,10 @@
     "redhat": {
       "iscsi_package": "iscsi-initiator-utils"
     },
-    "suse": {
-      "dkms_package": ""
-    },
     "gentoo": {
       "ccache_package": "dev-util/ccache",
       "curl": "net-misc/curl",
       "dhcp_client": "net-misc/dhcp",
-      "dkms_package": "",
       "extlinux": "sys-boot/syslinux",
       "git": "dev-vcs/git",
       "grub_bios": "sys-boot/grub",
@@ -31,7 +27,6 @@
   },
   "default": {
     "ccache_package": "ccache",
-    "dkms_package": "dkms",
     "iscsi_package": "open-iscsi"
   }
 }