gpu: vivante: Moved away options that are no longer inspected in uapi

After the uapi minimization, 9 out of 14 options used by uapi headers
are no longer used there, so move those option definitions to the
internal options header.
gpu: vivante: Moved gcdPOWEROFF_TIMEOUT option out of uapi

This option is enabled by default. If it was disabled, one element in
enum _gceCHIPPOWERSTATE was not included. Changed the enum header to
always include that element, whether the option is enabled or not.
gpu: vivante: Moved USE_NEW_LINUX_SIGNAL option out of uapi

This option is disabled by default. If it was enabled, one element in
struct _gcsHAL_INTERFACE was not included. Changed the driver header to
always include that element, whether the option is enabled or not.