Bug#891289: gcc-8: produces broken Build-Depends with nolang=biarch

[Helmut Grohne <helmut@subdivi.de>]

Source: gcc-8
Version: 8-20180218-1
Tags: patch
User: helmutg@debian.org
Usertags: rebootstrap
Control: block 666743 by -1

While working on coinstallable toolchains, I deactivated biarch to speed
up initial test builds and discovered that doing so produces broken
Build-Depends. debian/control.m4 lists GCC_MULTILIB_BUILD_DEP on a
single line and when nolang contains biarch, GCC_MULTILIB_BUILD_DEP
happens to become empty.  Thus Build-Depends contains a completely empty
line and various tools don't like that at all.

Thus I propose merging the line with the previous line, which is
guarantueed to be non-empty. Please consider applying the attached
patch.

Helmut

--- a/debian/control.m4
+++ b/debian/control.m4
@@ -71,8 +71,7 @@
   zlib1g-dev, SDT_BUILD_DEP
   bison (>= 1:2.3), flex, coreutils (>= 2.26) | realpath (>= 1.9.12), lsb-release, quilt
 ',`dnl native
-Build-Depends: DEBHELPER_BUILD_DEP DPKG_BUILD_DEP
-  GCC_MULTILIB_BUILD_DEP
+Build-Depends: DEBHELPER_BUILD_DEP DPKG_BUILD_DEP GCC_MULTILIB_BUILD_DEP
   LIBC_BUILD_DEP, LIBC_BIARCH_BUILD_DEP LIBC_DBG_DEP
   kfreebsd-kernel-headers (>= 0.84) [kfreebsd-any], linux-libc-dev [m68k],
   AUTO_BUILD_DEP BASE_BUILD_DEP