Made the QEMU IDE disk tolerate more power-mgmt commands, specifically:
	WIN_SETFEATURE(EN_AAM)	- enable automatic acoustic mgmt
	WIN_SETFEATURE(DIS_AAM)	- disable automatic acoustic mgmt
	WIN_SETFEATURE(DIS_APM)	- disable automatic power mgmt
	WIN_STANDBY
	WIN_SETIDLE1
	WIN_SLEEPNOW1
	WIN_STANDBY2
	WIN_SETIDLE2
	WIN_SLEEPNOW2
	WIN_STANDBYNOW2
These are all essentially no-ops, like existing support for EN_RLA (enable
read lookahead) and WIN_STANDBYNOW1.

This fixes a crash in the SLES9-SP3 64bit kernel when the powersaved was
started (with ACPI or ACM).  This guest really only needs EN_AAM, DIS_APM,
and WIN_SETIDLE1 support, but the others seemed sensible to include.

I've excluded EN_APM since I'm unsure of what that's agreeing to do.  It's
probably ok to include.

Signed-off-by: Ben Guthro <bguthro@virtualiron.com>
Signed-off-by: David Lively <dlively@virtualiron.com>