[llvm] [llvm][docs] Refresh Arm builtins cross compile guide (PR #150966)

[Eli Friedman via llvm-commits]

================
@@ -14,117 +14,113 @@ targets are welcome.
 
 The instructions in this document depend on libraries and programs external to
 LLVM, there are many ways to install and configure these dependencies so you
-may need to adapt the instructions here to fit your own local situation.
+may need to adapt the instructions here to fit your own situation.
 
 Prerequisites
 =============
 
-In this use case we'll be using cmake on a Debian-based Linux system,
-cross-compiling from an x86_64 host to a hard-float Armv7-A target. We'll be
+In this use case we will be using cmake on a Debian-based Linux system,
+cross-compiling from an x86_64 host to a hard-float Armv7-A target. We will be
 using as many of the LLVM tools as we can, but it is possible to use GNU
 equivalents.
 
- * ``A build of LLVM/clang for the llvm-tools and llvm-config``
- * ``A clang executable with support for the ARM target``
- * ``compiler-rt sources``
- * ``The qemu-arm user mode emulator``
- * ``An arm-linux-gnueabihf sysroot``
+You will need:
+ * A build of LLVM for the llvm-tools and ``llvm-config``.
+ * A clang executable with support for the ``ARM`` target.
+ * compiler-rt sources.
+ * The ``qemu-arm`` user mode emulator.
+ * An ``arm-linux-gnueabihf`` sysroot.
 
-In this example we will be using ninja.
+In this example we will be using ``ninja`` as the build tool.
 
-See https://compiler-rt.llvm.org/ for more information about the dependencies
+See https://compiler-rt.llvm.org/ for information about the dependencies
 on clang and LLVM.
 
 See https://llvm.org/docs/GettingStarted.html for information about obtaining
-the source for LLVM and compiler-rt. Note that the getting started guide
-places compiler-rt in the projects subdirectory, but this is not essential and
-if you are using the BaremetalARM.cmake cache for v6-M, v7-M and v7-EM then
-compiler-rt must be placed in the runtimes directory.
+the source for LLVM and compiler-rt.
 
 ``qemu-arm`` should be available as a package for your Linux distribution.
 
-The most complicated of the prerequisites to satisfy is the arm-linux-gnueabihf
+The most complicated of the prerequisites to is the ``arm-linux-gnueabihf``
----------------
efriedma-quic wrote:

"to is the" can't be right.

https://github.com/llvm/llvm-project/pull/150966