Set record sample rate to match playback sample rate.

Some hardware needs this; without it, recording defaults to 8kHz and
playback actually happens at 8kHz even though the playback sample rate
is set to 44.1kHz.  The iNovas

gcscaudio0 at pci0 dev 15 function 3: AMD Geode CS5536 Audio
gcscaudio0: interrupting at irq 11
gcscaudio0: ac97: Avance Logic unknown (0x414c4770) codec; headphone, 20 bit DAC, 18 bit ADC, no 3D stereo
gcscaudio0: ac97: ext id a07<AC97_23,AMAP,SPDIF,DRA,VRA>
audio0 at gcscaudio0: full duplex, playback, capture, mmap, independent

are an example; `independent' appears to be at least partially false.