Cleanup EVP_PKEY serialization #156

Job	Run time
GCC 4.8 - CMake 0 - FIPS 0	7m 30s
GCC 4.8 - CMake 0 - FIPS 1	7m 44s
GCC 5 - CMake 0 - FIPS 0	6m 17s
GCC 5 - CMake 0 - FIPS 1	9m 10s
GCC 7 - CMake 0 - FIPS 0	4m 10s
GCC 6 - CMake 0 - FIPS 0	6m 18s
GCC 7 - CMake 0 - FIPS 1	5m 42s
GCC 6 - CMake 0 - FIPS 1	13m 24s
GCC 8 - CMake 0 - FIPS 0	4m 5s
GCC 4.8 - CMake 1 - FIPS 0	7m 22s
GCC 8 - CMake 0 - FIPS 1	5m 31s
C-std ubuntu-latest - 11 - Force CMake 0	1m 49s
GCC 4.8 - CMake 1 - FIPS 1	7m 44s
GCC 7 - CMake 1 - FIPS 0	3m 55s
C-std ubuntu-latest - 11 - Force CMake 1	1m 42s
GCC 5 - CMake 1 - FIPS 0	6m 16s
GCC 7 - CMake 1 - FIPS 1	5m 3s
C-std ubuntu-latest - 99 - Force CMake 0	1m 54s
GCC 5 - CMake 1 - FIPS 1	8m 18s
C-std ubuntu-latest - 99 - Force CMake 1	1m 34s
GCC 8 - CMake 1 - FIPS 0	3m 44s
GCC 6 - CMake 1 - FIPS 0	6m 22s
C-std macos-13 - 11 - Force CMake 0	2m 11s
GCC 8 - CMake 1 - FIPS 1	5m 19s
GCC 6 - CMake 1 - FIPS 1	7m 34s
C-std macos-13 - 11 - Force CMake 1	2m 58s
C-std macos-13 - 99 - Force CMake 0	2m 18s
C-std macos-13 - 99 - Force CMake 1	2m 0s
C-std macos-14-xlarge - 11 - Force CMake 0	1m 33s
C-std macos-14-xlarge - 11 - Force CMake 1	1m 26s
C-std macos-14-xlarge - 99 - Force CMake 0	1m 27s
C-std macos-14-xlarge - 99 - Force CMake 1	1m 15s
C-std windows-latest - 11 - Force CMake 0	4m 34s
C-std windows-latest - 11 - Force CMake 1	4m 50s
C-std windows-latest - 99 - Force CMake 0	4m 44s
C-std windows-latest - 99 - Force CMake 1	4m 7s
	2h 51m 50s

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