Fix compilation errors with floating point is enabled and field widths are...

Fix compilation errors with floating point is enabled and field widths are disabled (I don't know why you would do that, but the code was wrong)

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4562 42af7a65-404d-4744-a932-0658087f49c3