ipa-reorder-for-locality - Adjust bootstrap-lto-locality and param to reduce compile time
This patch turns off -fipa-reorder-for-locality for -fprofile-generate because
it's not required and contributes to the bloated time taken by bootstrap. It
also reduces the default partition size by half; the increased number of
partitions speeds up LTRANS phase.
Bootstrapped and tested on aarch64-none-linux-gnu. OK for mainline?