MAINTAINERS: pci: add entry for Rust PCI code

Bjorn, Krzysztof and I agreed that I will maintain the Rust PCI code.
Therefore, create a new entry in the MAINTAINERS file.

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Link: https://lore.kernel.org/r/20250407133059.164042-1-dakr@kernel.org


[ Align Krzysztof's email address. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>