ci: force gcc use for crypto test

ci/build.yml

@@ -304,6 +304,7 @@ crypto build:
   needs: []
   variables:
     ADDRESS_SANITIZER: "1"
+    CC: gcc
   only:
     changes:
       - .gitlab-ci.yml

docs/ci/jobs.md

@@ -106,27 +106,27 @@ it is just a single binary file that you can execute directly.
 ### [crypto build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L301)
 Build of our cryptographic library, which is then incorporated into the other builds.
 
-### [legacy fw regular build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L330)
+### [legacy fw regular build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L331)
 
-### [legacy fw regular debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L346)
+### [legacy fw regular debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L347)
 
-### [legacy fw btconly build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L363)
+### [legacy fw btconly build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L364)
 
-### [legacy fw btconly debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L382)
+### [legacy fw btconly debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L383)
 
-### [legacy emu regular debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L403)
+### [legacy emu regular debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L404)
 Regular version (not only Bitcoin) of above.
 **Are you looking for a Trezor One emulator? This is most likely it.**
 
-### [legacy emu regular debug asan build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L418)
+### [legacy emu regular debug asan build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L419)
 
-### [legacy emu regular debug build arm](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L436)
+### [legacy emu regular debug build arm](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L437)
 
-### [legacy emu btconly debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L462)
+### [legacy emu btconly debug build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L463)
 Build of Legacy into UNIX emulator. Use keyboard arrows to emulate button presses.
 Bitcoin-only version.
 
-### [legacy emu btconly debug asan build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L479)
+### [legacy emu btconly debug asan build](https://github.com/trezor/trezor-firmware/blob/master/ci/build.yml#L480)
 
 ---
 ## TEST stage - [test.yml](https://github.com/trezor/trezor-firmware/blob/master/ci/test.yml)