REGTESTS: ssl: skip AWS-LC FIPS rejected crypto in ciphersuites/curves tests

REGTESTS: ssl: skip AWS-LC FIPS rejected crypto in ciphersuites/curves tests

Four reg-tests deliberately configure cryptographic material that
HAProxy's FIPS compliance checks reject when the SSL library runs in FIPS
mode, so they can never start a configuration there:

  - ssl_ciphersuites.vtc and quic/ssl_ciphersuites.vtc configure the
    TLS_CHACHA20_POLY1305_SHA256 ciphersuite, which is not FIPS-approved;
  - ssl_curves_selection.vtc, quic/ssl_curves_selection.vtc and
    ssl_curve_name.vtc, quic/ssl_curve_name.vtc configure the X25519
    group, which is likewise rejected.

Each then fails while parsing the configuration rather than on the
behaviour under test, which is why ssl_fips_check_ciphersuites(),
ssl_fips_check_curves() and their callers in src/ssl_sock.c exist in the
first place; the rejection is the expected outcome of the check, not a
defect in the test.

Skip those files with the fips_mode() config condition predicate already
used elsewhere in reg-tests/ssl (see "REGTESTS: ssl: skip tests broken by
FIPS mode"), so that they keep running against every non-FIPS SSL library
including OpenSSL and plain AWS-LC, and are only skipped when FIPS is
actually active.