usb: xhci-msm-hsic: Increase debug log buffer to 1024 entries

Debug log buffer is a circular buffer. Double the number of entries
to capture more events during crashes.

Change-Id: I978c5121ed3d536e1840698d8ac8d6e17c0c51d8
Signed-off-by: Vamsi Krishna <vskrishn@codeaurora.org>