egl: Unify the EGLint/EGLAttrib paths in eglCreateSync* (v3)

egl: Unify the EGLint/EGLAttrib paths in eglCreateSync* (v3)

Pre-patch, there were two code paths for parsing EGLSync attribute
lists: one path for old-style EGLint lists, used by eglCreateSyncKHR,
and another for new-style EGLAttrib lists, used by eglCreateSync (1.5)
and eglCreateSync64 (EGL_KHR_cl_event2).

There were two attrib_list parsing functions,
  _eglParseSyncAttribList(_EGLSync *sync, const EGLint *attrib_list)
  _eglParseSyncAttribList64(_EGLSync *sync, const EGLattrib *attrib_list)
This patch unifies the two attrib_list parsing functions into one,
  _eglParseSyncAttribList(_EGLSync *sync, const EGLattrib *attrib_list)

Many internal EGLSync function signatures had *two* attrib_list
parameters to accomodate both code paths: one parameter was an EGLint
list and other an EGLAttrib list. At most one of the parameters was
allowed to be non-null.  This patch removes the `EGLint *attrib_list`
parameter, leaving only the `EGLAttrib *attrib_list` parameter, for all
internal EGLSync functions.

v2:
  - Consistently use condition (sizeof(int_list[0]) ==
    sizeof(attrib_list[0])). [for emil]
v3:
  - Don't double-unlock the display in eglCreateSyncKHR.

Reviewed-by: Emil Velikov <emil.velikov@collabora.com> (v2)