FS#50481 add nano.spec specific newlib.h header file

PKGBUILD

@@ -3,7 +3,7 @@
 _target=arm-none-eabi
 pkgname=$_target-newlib
 pkgver=3.0.0.20180226
-pkgrel=1
+pkgrel=2
 _upstream_ver=$pkgver
 pkgdesc='A C standard library implementation intended for use on embedded systems (ARM bare metal)'
 arch=(any)
@@ -52,6 +52,8 @@ package() {
   cd "$srcdir"/build-nano
   make DESTDIR="$pkgdir" install -j1
   find "$pkgdir" -regex ".*/lib\(c\|g\|rdimon\)\.a" -exec rename .a _nano.a '{}' \;
+  install -d "$pkgdir"/usr/$_target/include/newlib-nano
+  install -m644 -t "$pkgdir"/usr/$_target/include/newlib-nano "$pkgdir"/usr/$_target/include/newlib.h
 
   cd "$srcdir"/build-newlib
   make DESTDIR="$pkgdir" install -j1