benchmarks/clpeak: update to 1.1.0.r2

• Switch to vendor install
• Drop unused RUN_DEPENDS
• Allow on more architectures

Changes: https://github.com/krrishnarraj/clpeak/compare/75c8746...1.1.0-rc2
Approved by: maintainer timeout (2 weeks)
Differential Revision: https://reviews.freebsd.org/D23821