8001460: build-infra: Linker warnings on macosx

Summary: Only linking against jvm variant specific dirs if they are expected to exist.
Reviewed-by: ohair

common/autoconf/toolchain.m4

@@ -938,10 +938,17 @@ else
         fi
     fi
     LDFLAGS_JDKLIB="${LDFLAGS_JDK} $SHARED_LIBRARY_FLAGS \
-                    -L${JDK_OUTPUTDIR}/lib${OPENJDK_TARGET_CPU_LIBDIR}/server \
-                    -L${JDK_OUTPUTDIR}/lib${OPENJDK_TARGET_CPU_LIBDIR}/client \
                     -L${JDK_OUTPUTDIR}/lib${OPENJDK_TARGET_CPU_LIBDIR}"
 
+    # On some platforms (mac) the linker warns about non existing -L dirs.
+    # Only add client dir if client is being built. Otherwise server should
+    # be enough
+    if test "x$JVM_VARIANT_CLIENT" = xtrue; then
+        LDFLAGS_JDKLIB="${LDFLAGS_JDKLIB} -L${JDK_OUTPUTDIR}/lib${OPENJDK_TARGET_CPU_LIBDIR}/client"
+    else
+        LDFLAGS_JDKLIB="${LDFLAGS_JDKLIB} -L${JDK_OUTPUTDIR}/lib${OPENJDK_TARGET_CPU_LIBDIR}/server"
+    fi
+
     LDFLAGS_JDKLIB_SUFFIX="-ljava -ljvm"
     if test "x$COMPILER_NAME" = xossc; then
         LDFLAGS_JDKLIB_SUFFIX="$LDFLAGS_JDKLIB_SUFFIX -lc"