Platforms/RaspberryPi: SMBIOS Type 2 and Type 3 fixes

Various fixes for SMBIOS Types 2 and 3:
 - Add LocationInChassis string to Type 2
 - Update Type 3 NumberofPowerCords to 1
 - Add ChassisHandle refernce to Type2. This requires moving the
   Type 3 population to happen before Type 2

Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Pete Batard <pete@akeo.ie>
Cc: Andrei Warkentin <awarkentin@vmware.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Signed-off-by: Samer El-Haj-Mahmoud <samer.el-haj-mahmoud@arm.com>
Reviewed-by: Andrei Warkentin <awarkentin@vmware.com>