Changes since v11.1

Build changes

• picom now depends on libepoxy for OpenGL symbol management.

Bug fixes

• Workaround a NVIDIA problem that causes high CPU usage after suspend/resume (#1172, #1168)
• Fix building on OpenBSD (#1189, #1188)
• Fix occasional freezes (#1040, #1145, #1166)
• Fix corner-radius-rules not applying sometimes (#1177)
• Fix window shader not having an effect when frame opacity is enabled (#1174)
• Fix binding root pixmap in case of depth mismatch (#984)