Add a libc for the arm-none-eabi compiler.

* The gcc_nolibc compiler is built first, it doesn't come with a C
library
* This compiler is then used to build the newlibc
* Finally, gcc is built again (the final version of the package) using
the newly built newlibc.

Also fix some paths so everything gets installed in
system/develop/tools/arm-none-eabi. This is the simplest way to go so
this particular gcc finds the includes there, without any risk of mixing
them up with actual includes for Haiku.

sys-libs/arm_none_eabi_newlib/arm_none_eabi_newlib-2.1.0.recipe

@@ -63,11 +63,11 @@ BUILD_PREREQUIRES="
 	cmd:make
 	cmd:makeinfo
 	cmd:${targetU}_ld$secondaryArchSuffix
-	${tagetU}_gcc_nolibc$secondaryArchSuffix
+	${targetU}_gcc_nolibc$secondaryArchSuffix
 "
 
 sourceDir=$(pwd)
-installDir="$prefix/$relativeInstallDir/develop"
+installDir="$prefix/$relativeInstallDir/develop/tools/"
 objectsDir=$(pwd)/../${portVersionedName}-obj
 
 BUILD()