Don't suppress using separate debug info when cross compiling

Don't suppress using separate debug info when cross compiling

The configure script currently automatically assumes that if you are cross
compiling, we should avoid trying to generate and strip separate debug
information due to toolchain limitations.

Historically there may have been good grounds for this, but it seems like
an aggressively pessimistic assumption which ignores the
standardization/advancement of embedded toolchains as a whole.

This assumption also extends to host compilers which deviate from the
automatically detected "platform" compiler, such as Clang.

Change-Id: Ifed2750325178bb5291d8ca1dde92925bfa36065
Reviewed-by: Girish Ramakrishnan <girish.1.ramakrishnan@nokia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>