tss2-tcti: tcti-libtpms: fix test failure on big-endian platform #1741

Job	Run time
scanbuild	6m 27s
build-test (ubuntu-18.04, gcc)	9m 10s
test-mbedtls (ubuntu-20.04)	3m 15s
test-tcti-config	13m 1s
build-test (ubuntu-18.04, clang)	7m 38s
test-mbedtls (ubuntu-22.04-mbedtls-3.1)	3m 42s
build-test (ubuntu-20.04, gcc)	7m 43s
build-test (ubuntu-20.04, clang)	4m 47s
build-test (fedora-32, gcc)	5m 15s
test-coverage	5m 3s
test-fuzz	2m 27s
build-test (fedora-32, clang)	7m 51s
build-test (opensuse-leap, gcc)	4m 51s
build-test (opensuse-leap, clang)	9m 27s
test-no-crypto-build	2m 3s
build-test (ubuntu-22.04, gcc)	9m 54s
build-test (ubuntu-22.04, clang)	5m 36s
build-test (alpine-3.15, gcc)	8m 5s
coverity-test	0s
build-test (alpine-3.15, clang)	7m 24s
	2h 3m 39s

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