t/nvmept_fdp: accommodate devices with many RUHS

t/nvmept_fdp: accommodate devices with many RUHS

Fio can only accept 128 placement IDs to write to. It is possible for
namespaces to have thousands of placement IDs. Adjust the standard tests
to acommodate this situation. Instead of just assuming that the device
has fewer than 128 placement IDs, change the expected RUAMW calculations
to also work for the case where the namespace has more than 128
placement IDs exceeds 128.

Also adjust the scheme test to work where there are more RUHS than the
max scheme entries allowed.

Signed-off-by: Vincent Fu <vincent.fu@samsung.com>