Pretend the SPIR ver needed by shuffles is 1.2

In reality the SPIR-V shuffles and ballot operations
require v1.3, but they seem to work with Intel's v1.2
implementation (likely due to the extensions).

Until v1.3 support is added to the driver, let's just pretend
these are v1.2 features to allow CHIPSPV warp-level functions
to compile.

Author: Pekka Jääskeläinen

lib/SPIRV/libSPIRV/SPIRVEntry.h

@@ -881,7 +881,7 @@ class SPIRVCapability : public SPIRVEntryNoId<OpCapability> {
     case CapabilityGroupNonUniformShuffle:
     case CapabilityGroupNonUniformShuffleRelative:
     case CapabilityGroupNonUniformClustered:
-      return static_cast<SPIRVWord>(VersionNumber::SPIRV_1_3);
+      return static_cast<SPIRVWord>(VersionNumber::SPIRV_1_2);
 
     case CapabilityNamedBarrier:
     case CapabilitySubgroupDispatch: