[LyX/master] Was forgetting this

[Enrico Forestieri]

commit 9b0e5215d935221c49ce97540bb0161290e72984
Author: Enrico Forestieri <for...@lyx.org>
Date:   Fri Jun 26 22:54:23 2015 +0200

    Was forgetting this

diff --git a/src/support/lstrings.cpp b/src/support/lstrings.cpp
index 3b903c8..0036d16 100644
--- a/src/support/lstrings.cpp
+++ b/src/support/lstrings.cpp
@@ -1407,7 +1407,6 @@ std::string formatFPNumber(double x)
        os << std::fixed;
        // Prevent outputs of 23.4200000000000017 but output small numbers
        // with at least 6 significant digits.
-       bool const neg = x < 0;
        double const logarithm = log10(abs(x));
        os << std::setprecision(max(6 - static_cast<int>(round(logarithm)), 0)) 
<< x;
        string result = os.str();