cc/gcc: remove 'sub-level' version form symbols

Now we use defconfig files to store the samples, we have to be a bit more
conservatives in the symbols names, so as to avoid gigantic version bumps
when updating sub-level versions from a package.

For example (using fictitious versions):
- in crosstool-NG 1.17.0, we choose:
- latest gcc is gcc-linaro-4.7-2012.10, which is the default for the
choice in the menuconfig
- gcc-linaro-4.6-2012.10 is selected
- so, sample has an explicit symbol for the selected gcc version, as it
is not the default
- we update to crosstool-NG 1.18.0:
- latest gcc version is gcc-linaro-4.7-2013.01
- gcc-linaro-46 has been updated to gcc-linaro-4.6-2013.01
- as the sample now has no *valid* symbol to set the gcc version, the
default is used, while we would have expected to still use the 4.6
release from linaro, not the 4.7

Get rid of sub-level (ie. the third digit sequence in versions) from the
symbols for linaro versions.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 # Companion tools config options

 if EXPERIMENTAL

 menu "Companion tools"

 comment "READ HELP before you say 'Y' below !!!"

 config COMP_TOOLS

     bool

     prompt "Build some companion tools"

     help

       Crosstool-NG relies on some external tools to be recent enough, namely:

         make = 3.81 (in some cases)

         m4 >= 1.4.12

         autoconf >= 2.63

         automake >= 1.10.2

         libtool >= 2.2.4

       If your system has older versions, we can build them for you,

       but you are strongly encouraged to update your system instead!

 if COMP_TOOLS

 config COMP_TOOLS_make

     bool

     prompt "make"

 config COMP_TOOLS_m4

     bool

     prompt "m4"

 config COMP_TOOLS_autoconf

     bool

     prompt "autoconf"

 config COMP_TOOLS_automake

     bool

     prompt "automake"

 config COMP_TOOLS_libtool

     bool

     prompt "libtool"

 endif

 endmenu

 endif