V4L/DVB (8877): b2c2 and bt8xx: udelay to mdelay

V4L/DVB (8877): b2c2 and bt8xx: udelay to mdelay

b2c2-flexcop, dvb/bt8xx and video/bt8xx fails to build on ARM with:

__bad_udelay is specifically designed on ARM to fail when udelay is
called in a bad way.  arch/arm/include/asm/delay.h has this to say
about __bad_udelay:

/*
 * This function intentionally does not exist; if you see references to
 * it, it means that you're calling udelay() with an out of range value.
 *
 * With currently imposed limits, this means that we support a max delay
 * of 2000us. Further limits: HZ<=1000 and bogomips<=3355
 */
extern void __bad_udelay(void);

Solution is to replace udelay by a mdelay and udelay with value less than 2000

Signed-off-by: Thierry MERLE <thierry.merle@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>