firmware/dmi: Report DMI Bios & EC firmware release

Some vendors like HPe or Dell, encode the release version of their BIOS
in the "System BIOS {Major|Minor} Release" fields of Type 0.

This information is used to know which bios release actually runs.
It could be used for some quirks, debugging sessions or inventory tasks.

A typical output for a Dell system running the 65.27 bios is :
	[root@t1700 ~]# cat /sys/devices/virtual/dmi/id/bios_release
	65.27
	[root@t1700 ~]#

Servers that have a BMC encode the release version of their firmware in the
 "Embedded Controller Firmware {Major|Minor} Release" fields of Type 0.

This information is used to know which BMC release actually runs.
It could be used for some quirks, debugging sessions or inventory tasks.

A typical output for a Dell system running the 3.75 bmc release is :
    [root@t1700 ~]# cat /sys/devices/virtual/dmi/id/ec_firmware_release
    3.75
    [root@t1700 ~]#

Signed-off-by: Erwan Velu <e.velu@criteo.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>