scripts: allow tuning any test build option
scripts: allow tuning any test build option

Any build option can be enabled or disabled by appending the end
of its name to the config name.
Examples:
	+INTRINSICS to enable CONFIG_RTE_FORCE_INTRINSICS
	~RXTX_CALLBACKS to disable CONFIG_RTE_ETHDEV_RXTX_CALLBACKS

These builtin (lowercase) options are also added for convenience:
	+debug to enable every debug options
	+default to set target machine as default

Signed-off-by: Thomas Monjalon <ee2fa8b2681c737f775687e475dcbf2028a412f1@6wind.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk