Remove the mmap len check, as github.com/google/pprof/issues/242 is fixed.
Remove the mmap len check, as github.com/google/pprof/issues/242 is fixed.

Change-Id: I2bb07b748d1b683ba7337194b21e428678531f8d
Reviewed-on: https://code-review.googlesource.com/30690
Reviewed-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Reviewed-by: Jonathan Amsterdam <e3d3698b2ccd5955e4adf250d0785062d0f9018b@google.com>

googleapis/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go