[realtek-ambz] Move C++ flags to SDK builder

builder/frameworks/realtek-ambz-sdk.py

@@ -27,6 +27,27 @@ env.Append(
         "-fomit-frame-pointer",
         "-fsigned-char",
     ],
+    CXXFLAGS=[
+        # borrowed from RtlDuino/development/rtl87xx/platform.txt
+        "-std=c++11",
+        "-mcpu=cortex-m4",
+        "-mthumb",
+        "-mfloat-abi=hard",
+        "-mfpu=fpv4-sp-d16",
+        "-g2",
+        "-w",
+        "-O2",
+        "-MMD",
+        "-fdata-sections",
+        "-ffunction-sections",
+        "-fmessage-length=0",
+        "-fno-common",
+        "-fno-exceptions",
+        "-fno-rtti",
+        "-fno-short-enums",
+        "-fomit-frame-pointer",
+        "-fsigned-char",
+    ],
     CPPDEFINES=[
         # LibreTuya configuration
         ("LT_HAS_LWIP", "1"),
@@ -59,7 +80,6 @@ env.Append(
         "-g",
         "--specs=nano.specs",
         "-nostartfiles",
-        "-Wl,-Map=" + join("$BUILD_DIR", "${PROGNAME}.map"),
         "-Os",
         "-Wl,--gc-sections",
         "-Wl,--cref",