platform/x86: dell-smbios: Rename dell-smbios source to dell-smbios-base

platform/x86: dell-smbios: Rename dell-smbios source to dell-smbios-base

BugLink: https://bugs.launchpad.net/bugs/1797304
This is being done to faciliate a later change to link all the dell-smbios
drivers together.

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
(cherry picked from commit 94f77cb16838065cdde514c97284481705c43200)
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Acked-by: Khalid Elmously <khalid.elmously@canonical.com>
Acked-by: Kleber Souza <kleber.souza@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>