Backport 2.16: Fix uninitialized variable in x509_crt

[pfalcon]

This patch fixes an issue we encountered with more stringent compiler
warnings. The signature_is_good variable has a possibility of being
used uninitialized. This patch moves the use of the variable to a
place where it cannot be used while uninitialized.

Signed-off-by: Andy Gross andy.gross@linaro.org

This is a backport to 2.16 of #2795

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Description

A few sentences describing the overall goals of the pull request's commits.

Status

READY/IN DEVELOPMENT/HOLD

Requires Backporting

When there is a bug fix, it should be backported to all maintained and supported branches.
Changes do not have to be backported if:

• This PR is a new feature\enhancement
• This PR contains changes in the API. If this is true, and there is a need for the fix to be backported, the fix should be handled differently in the legacy branch

Yes | NO
Which branch?

Migrations

If there is any API change, what's the incentive and logic for it.

YES | NO

Additional comments

Any additional information that could be of interest

Todos

• Tests
• Documentation
• Changelog updated
• Backported

Steps to test or reproduce

Outline the steps to test or reproduce the PR here.

[pfalcon]

This is backport of #2795 to mbedtls-2.16 branch. The only change is moving the ChangeLog entry to the appropriate place (next release).

[mpg]

Thanks for creating the backport! This looks good to me.

[k-stachowiak]

Thanks! LGTM.