Cleanup EVP_PKEY serialization #165

Job	Run time
GCC 7 - CMake 0 - FIPS 0	4m 6s
GCC 4.8 - CMake 0 - FIPS 0	7m 22s
GCC 7 - CMake 0 - FIPS 1	5m 45s
C-std ubuntu-latest - 11 - Force CMake 0	1m 50s
GCC 8 - CMake 0 - FIPS 0	3m 47s
GCC 4.8 - CMake 0 - FIPS 1	7m 32s
C-std ubuntu-latest - 11 - Force CMake 1	2m 35s
GCC 8 - CMake 0 - FIPS 1	5m 41s
GCC 5 - CMake 0 - FIPS 0	7m 54s
GCC 7 - CMake 1 - FIPS 0	4m 2s
C-std ubuntu-latest - 99 - Force CMake 0	1m 58s
GCC 5 - CMake 0 - FIPS 1	7m 53s
GCC 7 - CMake 1 - FIPS 1	5m 10s
C-std ubuntu-latest - 99 - Force CMake 1	1m 41s
GCC 6 - CMake 0 - FIPS 0	6m 42s
C-std macos-13 - 11 - Force CMake 0	3m 38s
GCC 8 - CMake 1 - FIPS 0	4m 34s
C-std macos-13 - 11 - Force CMake 1	2m 42s
GCC 6 - CMake 0 - FIPS 1	7m 37s
GCC 8 - CMake 1 - FIPS 1	5m 50s
C-std macos-13 - 99 - Force CMake 0	2m 34s
GCC 4.8 - CMake 1 - FIPS 0	6m 33s
C-std macos-13 - 99 - Force CMake 1	3m 14s
GCC 4.8 - CMake 1 - FIPS 1	8m 51s
C-std macos-14-xlarge - 11 - Force CMake 0	1m 29s
C-std macos-14-xlarge - 11 - Force CMake 1	1m 39s
GCC 5 - CMake 1 - FIPS 0	6m 7s
C-std macos-14-xlarge - 99 - Force CMake 0	2m 9s
GCC 5 - CMake 1 - FIPS 1	8m 23s
C-std macos-14-xlarge - 99 - Force CMake 1	2m 14s
GCC 6 - CMake 1 - FIPS 0	6m 16s
C-std windows-latest - 11 - Force CMake 0	4m 35s
GCC 6 - CMake 1 - FIPS 1	9m 44s
C-std windows-latest - 11 - Force CMake 1	4m 51s
C-std windows-latest - 99 - Force CMake 0	3m 35s
C-std windows-latest - 99 - Force CMake 1	3m 26s
	2h 53m 59s

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