[scudo] Fix GCC build after 212604 (#212904)

Change #212604 introduced an issue when building with gcc where it
complains there are "too few template-parameter-lists" (see log:

https://lab.llvm.org/buildbot/#/builders/131/builds/51269/steps/6/logs/stdio
)
This PR fixes the build.

Assisted-by: Automated tooling, human reviewed.
GitOrigin-RevId: aae5b3f2a92cc1c08a4bd65ba397fba5e37272fe
1 file changed