PCI: cadence: Search for MSI Capability with correct ID

907912c1 ("PCI: cadence: Use cdns_pcie_find_*capability() to avoid
hardcoding offsets") incorrectly searched for the MSI-X Capability ID
instead of the MSI Capability ID in cdns_pcie_ep_get_msi().

Search for PCI_CAP_ID_MSI, not PCI_CAP_ID_MSIX, to fix this problem.

Fixes: 907912c1 ("PCI: cadence: Use cdns_pcie_find_*capability() to avoid hardcoding offsets")
Reported-by: Sasha Levin <sashal@kernel.org>
Closes: https://lore.kernel.org/r/aOfMk9BW8BH2P30V@laps/


Signed-off-by: Hans Zhang <18255117159@163.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20251010144307.12979-1-18255117159@163.com