Merge branch 'fix-verifier-test-failures-in-verbose-mode'

Gregory Bell says:

====================
Fix verifier test failures in verbose mode

This patch series fixes two issues that cause false failures in the
BPF verifier test suite when run with verbose output (`-v`).

The following tests fail only when running the test_verifier in
verbose.

This leads to inconsistent results across verbose and
non-verbose runs.

Patch 1 addresses an issue where the verbose flag (`-v`) unintentionally
overrides the `opts.log_level`, leading to incorrect contents when checking
bpf_vlog in tests with `expected_ret == VERBOSE_ACCEPT`. This occurs when
running verbose with `-v` but not `-vv`

Patch 2 increases the size of the `bpf_vlog[]` buffer to prevent truncation
of large verifier logs, which was causing failures in several scale and
64-bit immediate tests.

Before patches:
./test_verifier | grep FAIL
Summary: 790 PASSED, 0 SKIPPED, 0 FAILED

./test_verifier -v | grep FAIL
Summary: 782 PASSED, 0 SKIPPED, 8 FAILED

./test_verifier -vv | grep FAIL
Summary: 787 PASSED, 0 SKIPPED, 3 FAILED

After patches:
./test_verifier -v | grep FAIL
Summary: 790 PASSED, 0 SKIPPED, 0 FAILED
./test_verifier -vv | grep FAIL
Summary: 790 PASSED, 0 SKIPPED, 0 FAILED

These fixes improve test reliability and ensure consistent behavior across
verbose and non-verbose runs.
====================

Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/cover.1747058195.git.grbell@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>