msm: ep-pcie: ipq: Enable global irq before link enum

Enabling global irq after link enumeration causes link
failure with IPQ host. Global irq is enabled before
enumeration for ipq host alone.

Change-Id: I20fa69c05bd3bc97fddea35e9e30833bca04c54b
Signed-off-by: Karthick Shanmugham <kartshan@codeaurora.org>