external/boringssl: cherry-pick crash fix

This change cherry-picks the following change from upstream:

commit 61dedd681501616de5928fe5c0eac6640d4de0c1
Author: Adam Langley <alangley@gmail.com>
Date:   Wed Feb 7 14:59:44 2018 -0800

    Don't crash when failing to set affine coordinates when the generator is missing.

    If a caller is in the process on constructing an arbitrary |EC_GROUP|,
    and they try to create an |EC_POINT| to set as the generator which is
    invalid, we would previously crash.

Test: cts -m CtsLibcoreTestCases -t com.android.org.conscrypt
Change-Id: I6183e5d103636c01ca1cb3659d9e62c4dd63458b
Merged-In: Id05fd03176db2282aecdf58311d6224ff5f8d89d
1 file changed