Previously, inject-hash would run the FIPS module in order to trigger a
failure and then extract the calculated hash value from the output. This
makes cross-compiling difficult because the build process needs to run a
binary for the target platform.

This change drops this step. Instead, inject-hash.go parses the object
file itself and calculates the hash without needing to run the module.

Change-Id: I2593daa03094b0a17b498c2e8be6915370669596
Reviewed-on: https://boringssl-review.googlesource.com/14964
Commit-Queue: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

Change-Id: Ic3a91ccd2c8cdc364740f256fdb8a7ff66177947
Reviewed-on: https://boringssl-review.googlesource.com/14506
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>