new port: benchmarks/flamegraph

[jmd]

Summary

A trivial port of Brendan Gregg's collection of flamegraph scripts (a lot of shebang-fixes). This will allow developers to visually profile output from, e.g., ljp and dtrace to locate CPU and memory hogs in workloads.

Test Plan

Compile tested on 10.3, 11.0, HEAAD i386, amd64

portlint -Aac clean

[jmd]

Change LOCALBASE in INSTALL to PREFIX. Change to proper pkg-plist instead of in Makefile PLIST as there are more than six entries.

[swills]

Approved