[complib:mpfr] Fix building MPFR in some weird cases

The tmul test uses a compiled-in input file in $(srcdir).
The problem is that the Makefile passes it unquoted. The C code
tries to stringify it using clever macros, which may *usually* work.

In my case the source directory was named:
.../toolchain-powerpc-e500v2-linux-gnuspe-1.0-2.fc10/.../tests
And guess what? During testing I found out the program fails because
it tries to open:
.../toolchain-powerpc-e500v2-1-gnuspe-1.0-2.fc10/.../tests

Yes, CPP tokenized the macro before stringifying it and not surprisingly
the 'linux' part was converted to 1.
[on Fedora-10: cpp (GCC) 4.3.2 20081105 (Red Hat 4.3.2-7)]

So the attached patch simplify the macros and pass the path as string
from the Makefile.

Manually backported from 1449:8ad2773e7ae3

diff -dur strace-4.5.15.orig/net.c strace-4.5.15/net.c

--- strace-4.5.15.orig/net.c	2006-12-13 20:57:23.000000000 +0100

+++ strace-4.5.15/net.c	2007-07-14 19:29:36.000000000 +0200

@@ -800,8 +800,12 @@

 #ifdef SOL_PACKET

 static const struct xlat sockpacketoptions[] = {

+#if defined(PACKET_ADD_MEMBERSHIP)

 	{ PACKET_ADD_MEMBERSHIP,	"PACKET_ADD_MEMBERSHIP"	},

+#endif

+#if defined(PACKET_DROP_MEMBERSHIP)

 	{ PACKET_DROP_MEMBERSHIP,	"PACKET_DROP_MEMBERSHIP"},

+#endif

 #if defined(PACKET_RECV_OUTPUT)

 	{ PACKET_RECV_OUTPUT,		"PACKET_RECV_OUTPUT"	},

 #endif