gcc: promote PKGVERSION and BUGURL options to toolchain level

This patch promotes the PKGVERSION and BUGURL options to toolchain level so that
all toolchain components supporting them can benefit from them.

These options are passed to configure through --with-pkgversion and
--with-bugurl.

They are supported by binutils 2.18+, gcc 4.3+, eglibc 2.9+ and gdb 7.0+.

Signed-off-by: "Benoît THÉBAUDEAU" <benoit.thebaudeau@advansee.com>

 # Super-H specific configuration file

 ## select ARCH_SUPPORTS_32

 ## select ARCH_DEFAULT_32

 ## select ARCH_USE_MMU

 ## select ARCH_SUPPORTS_BOTH_ENDIAN

 ## select ARCH_DEFAULT_LE

 ##

 ## help The Super-H architecture, as defined by:

 ## help     http://www.renesas.com/fmwk.jsp?cnt=superh_family_landing.jsp&fp=/products/mpumcu/superh_family/