oeqa/sdk: Improve Meson test

oeqa/sdk: Improve Meson test

The meson wrapper setup command detection is broken in the case of an
implicit setup command with an option with a space-separated argument,
but the test was not detecting it since the case was not covered.

Add the option `--warnlevel 1` to the meson command line to cover this
case.

Signed-off-by: Tom Hochstein <tom.hochstein@nxp.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>