Update kernel to builds 7518296

git log --first-parent -100 --oneline --no-decorate 877ad62bde6f..eaef435f4357:
eaef435f4357 ANDROID: kbuild: lto: sync update_lto_symversions with upstream
4d2f1b8fa9ba ANDROID: GKI: 7/2/2021 KMI update
fa0dc3e9ddc9 Revert "ANDROID: dmabuf: Add mmap_count to struct dmabuf"
641a578e56c3 ANDROID: Add CONFIG_CAN=y to gki_defconfig
794ef0c74c26 BACKPORT: tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers
14a5847c93c1 UPSTREAM: tracing: Declare newly exported APIs in include/linux/trace.h

Test: treehugger
Bug: 192989870
Change-Id: Iee8beb58ace3bcd2a0f2e123e73ba5fd1c57c6e6