Don't call the `ieee754sp_nanxcpt' and `ieee754dp_nanxcpt' sNaN quieting
handlers for a qNaN supplied to floating-point format conversions or
SQRT.S/SQRT.D instructions, or for a qNaN produced out of a negative
operand supplied to SQRT.S/SQRT.D instructions.  Return the qNaN right
away in these cases.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9687/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>