README: ARM Linux is supported.

Retested again on Ubuntu 12.04 armhf running in chroot on Samsung
ARM Chromebook (Cortex-A15).

README.md

@@ -38,9 +38,9 @@ The Unix version
 ----------------
 
 The "unix" port requires a standard Unix environment with gcc and GNU make.
-x86 and x64 architectures are supported (i.e. x86 32- and 64-bit). ARM to
-be confirmed. Porting to other architectures require writing some assembly
-code for the exception handling.
+x86 and x64 architectures are supported (i.e. x86 32- and 64-bit), as well
+as ARM. Porting to other architectures require writing some assembly code
+for the exception handling.
 
 To build: