vc/cavium/bdk/libdram: Print unknown voltages
volt_str is used to print information about the RAM configuration
in report_common_dimm(), so let's print out "unknown voltage" if the
voltage isn't recognized rather than a garbage value.
Change-Id: I8e85917fd682e166172fbf10597bde4a8a11dfc7
Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Found-by: Coverity CID 1393958, 1393982
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34576
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>