[CMake] CMAKE_SYSTEM_PROCESSOR = unknown for Intel Core Duo on Ubuntu 7.06

[James Bigler]

A colleague and I have a system with Ubuntu 7.06 installed.  I'm having some 
problems with the output of CMAKE_SYSTEM_PROCESSOR.  It is returning "unknown" 
instead of i686 or x86_64.  The processor is an Intel Core Duo.

I've used the 2.4.6 version installed with Ubuntu, as well as the binary and 
source builds of 2.4.6 downloaded from the website.

Here is the output of /proc/cpuinfo

% cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 14
model name      : Genuine Intel(R) CPU           T2500  @ 2.00GHz
stepping        : 8
cpu MHz         : 2000.000
cache size      : 2048 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 2
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 10
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov 
pat clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc pni monitor 
vmx est tm2 xtpr
bogomips        : 3994.46