Fixed broken build on newer gold linker with NaCl support
Fixed broken build on newer gold linker with NaCl support

On platforms with NaCl support, ld.gold -V will return a "elf_i386_nacl" in
addition to "elf_i386", which will make the build fail.

ManaPoustizadeh/OS-finalProject,ManaPoustizadeh/OS-finalProject,voytovichs/xv6-public,gw/xv6,phf/xv6-public,ManaPoustizadeh/OS-finalProject,shyandsy/xv6,shyandsy/xv6,gw/xv6,gw/xv6,phf/xv6-public,gw/xv6,ManaPoustizadeh/OS-finalProject,phf/xv6-public,voytovichs/xv6-public,voytovichs/xv6-public,voytovichs/xv6-public,shyandsy/xv6,phf/xv6-public,voytovichs/xv6-public,shyandsy/xv6,shyandsy/xv6,gw/xv6