cmd/compile: extend profiling-per-package-into-directory to other profiling flags
Also allow specification of "directory" with a trailing
path separator on the name. Updated suffix ".mprof" to ".memprof",
others are similarly disambiguated.
Change-Id: I2f3f44a436893730dbfe70b6815dff1e74885404
Reviewed-on: https://go-review.googlesource.com/c/go/+/542715
Run-TryBot: David Chase <drchase@google.com> Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>