debug symbols for package libmpfr-dev

 This development package provides the header files and the symbolic
 links to allow compilation and linking of programs that use the libraries
 provided in the libmpfr4 package.
 .
 MPFR provides a library for multiple-precision floating-point computation
 with correct rounding. The computation is both efficient and has a
 well-defined semantics. It copies the good ideas from the
 ANSI/IEEE-754 standard for double-precision floating-point arithmetic
 (53-bit mantissa).