USB: fix hcd interrupt disabling

Commit de85422b, 'USB: fix interrupt
disabling for HCDs with shared interrupt handlers' changed usb_add_hcd()
to strip IRQF_DISABLED from irqflags prior to calling request_irq()
with the justification that such a removal was necessary for shared
interrupts to work properly.  Unfortunately, the change in that commit
unconditionally removes the IRQF_DISABLED flag, causing problems on
platforms that don't use a shared interrupt but require IRQF_DISABLED.
This change adds a check for IRQF_SHARED prior to removing the
IRQF_DISABLED flag.

Fixes the PS3 system startup hang reported with recent Fedora and
OpenSUSE kernels.

Note that this problem is hidden when CONFIG_LOCKDEP=y (ps3_defconfig),
as local_irq_enable_in_hardirq() is defined as a null statement for
that config.

CC: stable <stable@kernel.org>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Stefan Becker <Stefan.Becker@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>