Fix sRGB exponent in Metal rendering#2846

jstone-lucasfilm merged 1 commit intoAcademySoftwareFoundation:mainAcademySoftwareFoundation/MaterialX:mainfrom

exavi:hotfix/meta-display-transform-use-spec-compliant-sRGB-gamma-exponentexavi/MaterialX:hotfix/meta-display-transform-use-spec-compliant-sRGB-gamma-exponentCopy head branch name to clipboard