Change parallel_lookup flag name for preparing release

This feature is eabled by default, the relevant flag is only used for
emergency rollback if we found any unexpected negative
impact.

This change is required because we don't want to accidentally
enable/disable this feature in the devices will old module installed.

Bug: 171010645
Test: atest
Change-Id: I44e7d51eb17b446f7f4316b296e1bbeff6ba05aa