MAINTAINERS: Add NXP S32G PCIe controller driver maintainer

MAINTAINERS: Add NXP S32G PCIe controller driver maintainer

Add a new entry for S32G PCIe controller driver.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
[bhelgaas: update to Ciprian Marian Costea per
https://lore.kernel.org/r/f38396c7-0605-4876-9ea6-0a179d6577c7@oss.nxp.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20251121164920.2008569-5-vincent.guittot@linaro.org