complibs/cloog: fix linking with libm

In Ubuntu 11.04 and 11.10, the default options for ld have changed.
--no-copy-dt-needed-entries and --as-needed are now enabled by default, which
causes errors like:

[EXTRA] Checking CLooG/ppl
[DEBUG] ==> Executing: 'make' '-j3' '-s' 'check'
[ALL ] Making check in .
[ALL ] config.status: creating include/cloog/cloog-config.h
[ALL ] config.status: include/cloog/cloog-config.h is unchanged
[ALL ] libtool: link: i686-build_pc-linux-gnu-gcc -Wall -fomit-frame-pointer
-pipe -o cloog cloog.o -L/<snip>/build/static/lib ./.libs/libcloog.a -lm
/<snip>/build/static/lib/libppl_c.a /<snip>/build/static/lib/libpwl.a
/<snip>/build/static/lib/libppl.a /<snip>/build/static/lib/libgmpxx.a
/<snip>/build/static/lib/libgmp.a -lstdc++
[ALL ] /usr/bin/ld: /<snip>/build/static/lib/libppl.a(MIP_Problem.o):
undefined reference to symbol 'sqrt@@GLIBC_2.0'
[ALL ] /usr/bin/ld: note: 'sqrt@@GLIBC_2.0' is defined in DSO
/usr/lib/gcc/i686-linux-gnu/4.6.1/../../../i386-linux-gnu/libm.so so try adding
it to the linker command line
[ALL ] /usr/lib/gcc/i686-linux-gnu/4.6.1/../../../i386-linux-gnu/libm.so:
could not read symbols: Invalid operation
[ALL ] collect2: ld returned 1 exit status
[ERROR] make[2]: *** [cloog] Error 1
[ERROR] make[1]: *** [check-recursive] Error 1

See:
https://wiki.ubuntu.com/NattyNarwhal/ToolchainTransition

This patch fixes these errors by placing '-lm' at the right place on the command
line as libppl requires libm when linking cloog.

Signed-off-by: "Benoît Thébaudeau" <benoit.thebaudeau@advansee.com>

 diff -durN binutils-2.21.1.orig/ld/emultempl/elf32.em binutils-2.21.1/ld/emultempl/elf32.em

 --- binutils-2.21.1.orig/ld/emultempl/elf32.em	2011-06-27 09:39:14.000000000 +0200

 +++ binutils-2.21.1/ld/emultempl/elf32.em	2011-09-12 13:39:08.808908274 +0200

 @@ -1272,6 +1272,8 @@

  	      && command_line.rpath == NULL)

  	    {

  	      lib_path = (const char *) getenv ("LD_RUN_PATH");

 +	      if ((lib_path) && (strlen (lib_path) == 0))

 +	      	lib_path = NULL;

  	      if (gld${EMULATION_NAME}_search_needed (lib_path, &n,

  						      force))

  		break;

 @@ -1499,6 +1501,8 @@

    rpath = command_line.rpath;

    if (rpath == NULL)

      rpath = (const char *) getenv ("LD_RUN_PATH");

 +  if ((rpath) && (strlen (rpath) == 0))

 +  	rpath = NULL;

    for (abfd = link_info.input_bfds; abfd; abfd = abfd->link_next)

      if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)