Increase InlineSmallCode default from 1000 to 2500 for RISC-V

The current default value of InlineSmallCode on RISC-V is 1000. I witnessed notable performance improvement increasing this value to 2000 when running the Renaissance benchmark.

I have also tested other possible values like 1500 and 2500, but the numbers say show 2000 would outperform those values in most of the cases.

And I can verify no regressions across at least following benchmarks:

- Dacapo
- SPECjvm2008
- SPECjbb2005
- SPECjbb2015