PCI: qcom-ep: Mask PTM_UPDATING interrupt

When PTM is enabled, PTM_UPDATING interrupt will be fired for each PTM
context update, which will be once every 10ms in the case of auto context
update. Since the interrupt is not strictly needed for making use of PTM,
mask it to avoid the overhead of processing it.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Link: https://patch.msgid.link/20250505-pcie-ptm-v4-4-02d26d51400b@linaro.org