debug/gdb: pump gdb to version 7.7

pump gdb to version 7.7

Signed-off-by: '"Daniel Zimmermann" <netzimme@gmail.com>'
[yann.morin.1998@free.fr: remove superfluous empty lines]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Message-Id: <a1bcc8a58a4613f0b8bf.1392475799@haus-VirtualBox>
Patchwork-Id: 320657

reporter_name="dsreed on freenode/#crosstool-ng"

reporter_url=""

reporter_comment="Enables experimental support for VFP/NEON hardware floating point."