pixelstats: move learning/model load path to sysfs Reporting learning(relaxation) and model loading once a day * learning and model loading path moved from uevent to sysfs collector. Bug: 329124192 Signed-off-by: Chungro Lee <chungro@google.com> (cherry picked from https://googleplex-android-review.googlesource.com/q/commit:e0d7a249370a93828b128cbffbab7ca9237cad90) Merged-In: I91039ce3a8ee4630a76113ef7ae6be3bc6908f64 Change-Id: I91039ce3a8ee4630a76113ef7ae6be3bc6908f64