Disable stack protector for BIOS

Some distro GCCs (like Ubuntu) enable stack protection by default.  Since the
BIOS doesn't link against libgcc, this results in undefined references unless
the stack protector is disabled.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

diff --git a/bios/Makefile.in b/bios/Makefile.in
index af674b4..5c7bd4f 100644
--- a/bios/Makefile.in
+++ b/bios/Makefile.in
@@ -41,7 +41,7 @@ RANLIB = @RANLIB@
 
 BCC = bcc
 GCC = gcc
-GCC32 = gcc -m32
+GCC32 = gcc -m32 -fno-stack-protector
 AS86 = as86
 
 BX_INCDIRS = -I.. -I$(srcdir)/.. -I../iodev -I$(srcdir)/../iodev