SettingsActivity: Get profile parent using UserManager.getProfileParent

In the headless system user mode(hsum) non-primary users can also have a profile.
The existing implementation in SettingsActivity always gets the primary user as the profile parent, refactored the implementation to get profile parent using UserManager.getProfileParent.

Test: NA
Bug: 267162079
Change-Id: I2af581a4b7e3320f9351b862b7be3ef141b744b7
1 file changed