Treat both negative and zero return values from clk_round_rate()
as errors. This is needed since subsequent patches will convert
clk_round_rate()'s return value to be an unsigned type, rather
than a signed type, since some clock sources can generate rates higher
than (2^31)-1 Hz.
Eventually, when calling clk_round_rate(), only a return value of
zero will be considered a error. All other values will be
considered valid rates. The comparison against values less than
0 is kept to preserve the correct behavior in the meantime.
Signed-off-by: Paul Walmsley <firstname.lastname@example.org>
Acked-by: Hans-Christian Egtvedt <email@example.com>
Signed-off-by: Takashi Iwai <firstname.lastname@example.org>