SCons: Remove redundant -fomit-frame-pointer and -ftree-vectorize

- `-fomit-frame-pointer` is included automatically by both GCC and
  Clang in `-O1` and above.
- `-ftree-vectorize` is included automatically by GCC in `-O2` and
  beyond, and seems always enabled by Clang.

Closes godotengine#66296. See that issue for a detailed investigation.

(cherry picked from commit c5c3d13)

platform/android/detect.py

@@ -126,11 +126,10 @@ def configure(env):
             # `-O2` is more friendly to debuggers than `-O3`, leading to better crash backtraces
             # when using `target=release_debug`.
             opt = "-O3" if env["target"] == "release" else "-O2"
-            env.Append(CCFLAGS=[opt, "-fomit-frame-pointer"])
+            env.Append(CCFLAGS=[opt])
         elif env["optimize"] == "size":  # optimize for size
             env.Append(CCFLAGS=["-Oz"])
         env.Append(CPPDEFINES=["NDEBUG"])
-        env.Append(CCFLAGS=["-ftree-vectorize"])
     elif env["target"] == "debug":
         env.Append(LINKFLAGS=["-O0"])
         env.Append(CCFLAGS=["-O0", "-g", "-fno-limit-debug-info"])

platform/iphone/detect.py

@@ -54,10 +54,10 @@ def configure(env):
             # `-O2` is more friendly to debuggers than `-O3`, leading to better crash backtraces
             # when using `target=release_debug`.
             opt = "-O3" if env["target"] == "release" else "-O2"
-            env.Append(CCFLAGS=[opt, "-ftree-vectorize", "-fomit-frame-pointer"])
+            env.Append(CCFLAGS=[opt])
             env.Append(LINKFLAGS=[opt])
         elif env["optimize"] == "size":  # optimize for size
-            env.Append(CCFLAGS=["-Os", "-ftree-vectorize"])
+            env.Append(CCFLAGS=["-Os"])
             env.Append(LINKFLAGS=["-Os"])
 
     elif env["target"] == "debug":

platform/osx/detect.py

@@ -43,9 +43,9 @@ def configure(env):
 
     if env["target"] == "release":
         if env["optimize"] == "speed":  # optimize for speed (default)
-            env.Prepend(CCFLAGS=["-O3", "-fomit-frame-pointer", "-ftree-vectorize"])
+            env.Prepend(CCFLAGS=["-O3"])
         elif env["optimize"] == "size":  # optimize for size
-            env.Prepend(CCFLAGS=["-Os", "-ftree-vectorize"])
+            env.Prepend(CCFLAGS=["-Os"])
         if env["arch"] != "arm64":
             env.Prepend(CCFLAGS=["-msse2"])