[parted-devel] [PATCH] build: avoid configure-time syntax error

[Jim Meyering]

Building on an ubuntu system without devmapper devel libraries,
I saw this failure:

  ./configure: line 264: return: but: numeric argument required
  ./configure: line 24783: --enable-device-mapper: command not found
  configure: error: libdevmapper could not be found

Then, looking at configure.ac, I found many other quoting problems.
This fixes most of them: