docs: fix info about bootstrapping

swiftlang#62017

Author: eeckstein

docs/HowToGuides/GettingStarted.md

@@ -243,10 +243,6 @@ Phew, that's a lot to digest! Now let's proceed to the actual build itself!
        --skip-ios --skip-watchos --skip-tvos --swift-darwin-supported-archs "$(uname -m)" \
        --sccache --release-debuginfo --swift-disable-dead-stripping
      ```
-     > **Warning**  
-     > On Macs with Apple silicon (arm64), pass `--bootstrapping=off`.
-     > (https://github.com/apple/swift/issues/62017)
-
    - Linux:
      ```sh
      utils/build-script --release-debuginfo --skip-early-swift-driver \
@@ -257,7 +253,8 @@ Phew, that's a lot to digest! Now let's proceed to the actual build itself!
 
    > **Note**  
    > If you aren't planning to edit the parts of the compiler that are written
-   > in Swift, pass `--bootstrapping=off` to speed up local development.
+   > in Swift, pass `--bootstrapping=hosttools` to speed up local development.
+   > This requires a recent Xcode and/or swift toolchain to be installed.
 
    This will create a directory `swift-project/build/Ninja-RelWithDebInfoAssert`
    containing the Swift compiler and standard library and clang/LLVM build artifacts.
@@ -463,7 +460,7 @@ Now that you have made some changes, you will need to rebuild...
 
 To rebuild the compiler:
 ```sh
-ninja -C ../build/Ninja-RelWithDebInfoAssert/swift-macosx-$(uname -m) swift-frontend
+ninja -C ../build/Ninja-RelWithDebInfoAssert/swift-macosx-$(uname -m) bin/swift-frontend
 ```
 
 To rebuild everything, including the standard library: