Regression: Minor depth-like regression multiple games (#8984)

[Xcedf]

Found a little regression of #8984 depth like looking issue, games affected: God of War 3, Metal Gear Solid 4, maybe others
47a9bba - the exact commit which caused issue

GoW3:
Screen on build with regression

Screen with broken commit reverted

MGS4:
https://youtu.be/aY7Rx7C947k

Logs:
GoW3 - build with the issue:
RPCS3.log.gz
GoW3 - build with reverted commit:
RPCS3.log.gz
MGS4 - build with the issue:
RPCS3.log.gz
MGS4 - build with reverted commit:
RPCS3.log.gz

Render docs:
GoW3 - build with the issue:
https://mega.nz/file/SIRX0YzL#s5-yjK73uvfl31LDvbA2lLmdKxuiaTPJipMTGhc8XaM
GoW3 - build with reverted commit:
https://mega.nz/file/XQQSHZBL#b3aIxEETETG-W67uTBRFeQCf0JCN0IcNZpNDUEBYTDo
MGS4 - build with the issue:
https://mega.nz/file/7RpTlAJR#8g_EPzQVIamdTeDquAXAAUpLQoUGdNH9cY48WzodJSk
MGS4 - build with reverted commit:
https://mega.nz/file/mZRlVSjA#29iLRzOY5xGSCfJlTtNlJfUbdIPmt7cYIRRbHgQI6J0

Rsx capturess:
GoW3 - build with the issue:
https://mega.nz/file/GNZnkYCT#7b_0oJVoo40-3S6kihrAB52K1bEgxlpcU_i4LBmrUBA
GoW3 - build with reverted commit:
https://mega.nz/file/WJoVxapQ#n6vLqA47e-C1ppssZWFX_hRF6iNt3PaI3jMvRZr09S4
MGS4 - build with the issue:
https://mega.nz/file/CIYAQRyD#rO4DsZcn4tXvDzzqFkLU0SR15j3PfOXnxppeCHbrpQY
MGS4 - build with reverted commit:
https://mega.nz/file/DFZCwB5S#G0TO6wUAImJ59KE0oHous5jMOyaK9j8atLiJPKlUq5o

My PC:
i9 9900k, Gtx 1070, Driver ver. 456.38

[kd-11]

Known issue with hardware-dependent OpQuantizeToF16 instruction not being up to required precision. Quite unfortunate as it basically nearly halves the size of emitted bytecode for the GPU drastically lowering compile times as well as ingame performance. I don't think we can go back to the old method as it was precise but really slow, I'll have to do SPIR instruction sequence injection for this one.

[Xcedf]

@kd-11 I'm totally agree, old method is not an option, #8984 nicely improved performance in GoW3 and i guess others as well.