Add support for x86_64.

PR: 348

Configure

@@ -392,6 +392,7 @@ my %table=(
 "linux-s390",	"gcc:-DB_ENDIAN -DTERMIO -DNO_ASM -O3 -fomit-frame-pointer -Wall::-D_REENTRANT::-ldl:BN_LLONG::::::::::dlfcn:linux-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",
 "linux-s390x",	"gcc:-DB_ENDIAN -DTERMIO -DNO_ASM -O3 -fomit-frame-pointer -Wall::-D_REENTRANT::-ldl:SIXTY_FOUR_BIT_LONG::::::::::dlfcn:linux-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",
 "linux-ia64",   "gcc:-DL_ENDIAN -DTERMIO -O3 -fomit-frame-pointer -Wall::-D_REENTRANT::-ldl:SIXTY_FOUR_BIT_LONG RC4_CHUNK RC4_CHAR:asm/ia64.o:::::::::dlfcn:linux-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",
+"linux-x86_64", "gcc:-DL_ENDIAN -DNO_ASM ::-D_REENTRANT::-ldl:SIXTY_FOUR_BIT_LONG::::::::::dlfcn:linux-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",
 "NetBSD-sparc",	"gcc:-DTERMIOS -O3 -fomit-frame-pointer -mv8 -Wall -DB_ENDIAN::(unknown):::BN_LLONG MD2_CHAR RC4_INDEX DES_UNROLL::::::::::dlfcn:bsd-gcc-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",
 "NetBSD-m68",	"gcc:-DTERMIOS -O3 -fomit-frame-pointer -Wall -DB_ENDIAN::(unknown):::BN_LLONG MD2_CHAR RC4_INDEX DES_UNROLL::::::::::dlfcn:bsd-gcc-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",
 "NetBSD-x86",	"gcc:-DTERMIOS -O3 -fomit-frame-pointer -m486 -Wall::(unknown):::BN_LLONG ${x86_gcc_des} ${x86_gcc_opts}::::::::::dlfcn:bsd-gcc-shared:-fPIC::.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)",

config

@@ -585,6 +585,7 @@ EOF
   arm*-*-linux2) OUT="linux-elf-arm" ;;
   s390-*-linux2) OUT="linux-s390" ;;
   s390x-*-linux?) OUT="linux-s390x" ;;
+  x86_64-*-linux?) OUT="linux-x86_64" ;;
   *-*-linux2) OUT="linux-elf"
 	if [ "$GCCVER" -gt 28 ]; then
           if grep '^model.*Pentium' /proc/cpuinfo >/dev/null ; then