Added fuzzers for libkeymaster4support

This patch adds following fuzz targets: keymaster4_attestation_fuzzer, keymaster4_authSet_fuzzer and keymaster4_utils_fuzzer

Test: ./keymaster4_attestation_fuzzer
Test: ./keymaster4_authSet_fuzzer
Test: ./keymaster4_utils_fuzzer
Bug: 189053968

Change-Id: Ieca5ba012f395a25cca9e37856d197031daf7dd9
6 files changed