* testsuite/sexp-format-test.c: Include bignum.h only if HAVE_LIBGMP.

* testsuite/rsa-encrypt-test.c: Include rsa.h only if WITH_PUBLIC_KEY.
* testsuite/pkcs1-test.c: Include pkcs1.h only if WITH_PUBLIC_KEY.

Rev: src/nettle/testsuite/pkcs1-test.c:1.2
Rev: src/nettle/testsuite/rsa-encrypt-test.c:1.4
Rev: src/nettle/testsuite/sexp-format-test.c:1.8