cc/gcc: add gcc 4.7.2

cc/gcc: add gcc 4.7.2

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Message-ID: <5869423.KezhlrYYmc@flexo>
PatchWork-ID: 185750

reporter_name="Yann E. MORIN"

reporter_url="http://ymorin.is-a-geek.org/projects/crosstool"

reporter_comment="EXPERIMENTAL MIPS-64 n64 toolchain."