staging: sm750fb: Fix of long line in makefile variable

A simple fix of long line in makefile variable assignment.
Found using checkpatch.pl.

Signed-off-by: R Veera Kumar <vkor@vkten.in>
Link: https://lore.kernel.org/r/20200319095024.GA2970@tulip.local
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: add missing SPDX lines to Makefile files

There are a few remaining drivers/staging/*/Makefile files that do not
have SPDX identifiers in them. Add the correct GPL-2.0 identifier to
them to make scanning tools happy.

Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: sm750fb: Merge ddk750_help.* into ddk750_chip.*.

The file ddk750_help.c contained only one function declaration,
so it was merged into ddk750_chip.c to simplify the driver.

Also, ddk750_help.h was merged into ddk750_chip.h to keep consistency.

With these changes a few global variables are removed and the function
ddk750_set_mmio is rewritten, so its purpose in the code is clearer.

Signed-off-by: Elise Lennion <elise.lennion@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: sm750fb: add sm750 to staging

sm750 of Silicon Motion is pci-e display controller device and has
features like dual display and 2D acceleration. This patch adds the
driver to staging.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>