lcms2: updated to 2.11

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2.11 Maintenance release
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Fixed __cpuid() on fast float plugin to allow gnu gcc
Fixed copy alpha bounds check
Fixed data race condition on contexts pool
Fixed LUT16 write matrix on multichannel V2 profiles

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2.10 Featured release
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Added a compilation toggle to remove "register" keyword in API.
Previously commercial, fast_float plug-in is now released as open source under GPL3 license.
MD5 functions are now accesible through plug-in API.
Added support for Visual Studio 2019
Bug fixing.

(adam)