main/build-base: configure scripts often expect file to work

main/build-base/APKBUILD

 # Maintainer: Natanael Copa <ncopa@alpinelinux.org>
 pkgname=build-base
 pkgver=0.5
-pkgrel=0
+pkgrel=1
 url=http://dev.alpinelinux.org/cgit
 pkgdesc="Meta package for build base"
-depends="binutils gcc g++ make libc-dev fortify-headers"
+depends="binutils file gcc g++ make libc-dev fortify-headers"
 if [ "$CHOST" != "$CTARGET" ]; then
 	pkgname="$pkgname-$CTARGET_ARCH"
 	pkgdesc="$pkgdesc ($CTARGET_ARCH)"