perf tools: Drop requirement for libstdc++.so for libopencsd check

It's possible to link against libopencsd_c_api without having
libstdc++.so available, only libstdc++.so.6.0.28 (or whatever version is
in use) needs to be available. The same holds true for libopencsd.so.
When -lstdc++ (or -lopencsd) is explicitly passed to the linker however
the .so file must be available.

So wrap adding the dependencies into a check for static linking that
actually requires adding them all. The same construct is already used
for some other tests in the same file to reduce dependencies in the
dynamic linking case.

Fixes: 573cf5c9a1 ("perf build: Add missing -lstdc++ when linking with libopencsd")
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Cc: Adrian Bunk <bunk@debian.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Branislav Rankov <branislav.rankov@arm.com>
Cc: Diederik de Haas <didi.debian@cknow.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/all/20211203210544.1137935-1-uwe@kleine-koenig.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile.config

@@ -144,7 +144,10 @@ FEATURE_CHECK_LDFLAGS-libcrypto = -lcrypto
 ifdef CSINCLUDES
   LIBOPENCSD_CFLAGS := -I$(CSINCLUDES)
 endif
-OPENCSDLIBS := -lopencsd_c_api -lopencsd -lstdc++
+OPENCSDLIBS := -lopencsd_c_api
+ifeq ($(findstring -static,${LDFLAGS}),-static)
+  OPENCSDLIBS += -lopencsd -lstdc++
+endif
 ifdef CSLIBS
   LIBOPENCSD_LDFLAGS := -L$(CSLIBS)
 endif