tests/sprintf: Test picolibc inexact floating point printf

Picolibc has two floating point output modules, the default, "exact",
module which meets the ISO/IEC 9899:2011 specification and a smaller
"inexact" version which does not meet those specifications. Add a test for
this latter version to make sure it meets some modest Zephyr requirements.

Signed-off-by: Keith Packard <keithp@keithp.com>
1 file changed