perf test trace_summary: Skip --bpf-summary tests if no libbpf

perf test trace_summary: Skip --bpf-summary tests if no libbpf

If perf is built without libbpf (e.g. NO_LIBBPF=1) then the
--bpf-summary perf trace tests will fail.

Skip the tests as this is expected behavior.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Howard Chu <howardchu95@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20250528032637.198960-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>