bhyve nvme: Fix LBA out-of-range calculation

[chuck]

Summary

The LBA out-of-range calculation was off by 1 because it did not account
for the Starting LBA being zero-based.

Fixes UNH ILO 16.0 Test 2.3, Cases 2, 4, and 5 and Test 2.4, Cases 2, 4,
and 5.

[allanjude]

Reviewed By: allanjude

[chuck]

Fix regression reported in Alma Linux + Windows

[jason_tubnor.net]

This patch fixed regression that was discovered during workload testing across various guest operating systems (as pointed out by @chuck above).

Tested and confirmed working on the following guest platforms with 14.0-CURRENT (20211223):

OpenBSD 6.9 - NVMe read/write OK
Windows 10 - NVMe read/write OK
Windows Server 2022 - NVMe read/write OK
Alma Linux 8.5 - NVMe read/write OK
FreeBSD 13.0 - NVMe read/write OK

[allanjude]

Reviewed by: allanjude