drm/vmwgfx: replace idr_init() by idr_init_base()

idr_init() uses base 0 which is an invalid identifier for this driver.
The idr_alloc for this driver uses 1 as start value for ID range. The
new function idr_init_base allows IDR to set the ID lookup from base 1.
This avoids all lookups that otherwise starts from 0 since 0 is always
unused / available.

References: commit 6ce711f2

 ("idr: Make 1-based IDRs more efficient")

Signed-off-by: Deepak R Varma <mh12gx2825@gmail.com>
Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105190718.GA89863@localhost