tools build: Remove libbpf-strings feature test

The feature test is unnecessary as the LIBBPF_CURRENT_VERSION_GEQ(1,7)
macro can be used instead. The only use was in perf and this is now
removed.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: captain5050

tools/build/Makefile.feature

@@ -123,7 +123,6 @@ FEATURE_TESTS_EXTRA :=                  \
          llvm                           \
          clang                          \
          libbpf                         \
-         libbpf-strings                 \
          libpfm4                        \
          libdebuginfod			\
          clang-bpf-co-re		\

tools/build/feature/Makefile

@@ -56,7 +56,6 @@ FILES=                                          \
          test-lzma.bin                          \
          test-bpf.bin                           \
          test-libbpf.bin                        \
-         test-libbpf-strings.bin                \
          test-get_cpuid.bin                     \
          test-sdt.bin                           \
          test-cxx.bin                           \
@@ -328,9 +327,6 @@ $(OUTPUT)test-bpf.bin:
 $(OUTPUT)test-libbpf.bin:
 	$(BUILD) -lbpf
 
-$(OUTPUT)test-libbpf-strings.bin:
-	$(BUILD)
-
 $(OUTPUT)test-sdt.bin:
 	$(BUILD)