rust: pci: inline several tiny functions

rust: pci: inline several tiny functions

Several previous commits added Vendor and Class functionality. As part
of that, the new functions were inlined where appropriate. But that left
this file with inconsistent use of inlining. Fix that by inlining the
remaining items that should be.

Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Elle Rhumsaa <elle@weathered-steel.dev>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/r/20250829223632.144030-7-jhubbard@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>