[llvm] [Offload] Add new llvm-liboffload-device-info tool (PR #155626)

[Ross Brunton via llvm-commits]

RossBrunton wrote:

Output on my system:

```
Liboffload Version: 0.0.1
Num Devices: 2

[gfx1100]
Platform Name: AMDGPU
Platform Vendor Name: Unknown platform vendor
Platform Version: v0.0.1
Platform Backend: AMDGPU
Type: GPU
Driver Version: 1.14
Max Work Group Size: 1024
Max Work Group Size Per Dimension: {x: 1024, y: 1024, z: 1024}
Vendor ID: 4130
Num Compute Units: 80
Max Clock Frequency: 1927MHz
Memory Clock Rate: 1124MHz
Address Bits: 64
Max Mem Allocation Size: 17163091968B
Global Mem Size: 17163091968B
Single Precision Floating Point Capability: 127 { CORRECTLY_ROUNDED_DIVIDE_SQRT ROUND_TO_NEAREST ROUND_TO_ZERO ROUND_TO_INF INF_NAN DENORM FMA }
Double Precision Floating Point Capability: 127 { CORRECTLY_ROUNDED_DIVIDE_SQRT ROUND_TO_NEAREST ROUND_TO_ZERO ROUND_TO_INF INF_NAN DENORM FMA }
Half Precision Floating Point Capability: 0 { }
Native Vector Width For Char: 1
Native Vector Width For Short: 1
Native Vector Width For Int: 1
Native Vector Width For Long: 1
Native Vector Width For Float: 1
Native Vector Width For Double: 1
Native Vector Width For Half: 0

[Virtual Host Device]
Platform Name: Host
Platform Vendor Name: Unknown platform vendor
Platform Version: v0.0.1
Platform Backend: HOST
Type: HOST
Driver Version: 22.0.0git
Max Work Group Size: 1
Max Work Group Size Per Dimension: {x: 1, y: 1, z: 1}
Vendor ID: 0
Num Compute Units: 1
Max Clock Frequency: 64MHz
Memory Clock Rate: 64MHz
Address Bits: 64
Max Mem Allocation Size: 0B
Global Mem Size: 0B
Single Precision Floating Point Capability: 127 { CORRECTLY_ROUNDED_DIVIDE_SQRT ROUND_TO_NEAREST ROUND_TO_ZERO ROUND_TO_INF INF_NAN DENORM FMA }
Double Precision Floating Point Capability: 127 { CORRECTLY_ROUNDED_DIVIDE_SQRT ROUND_TO_NEAREST ROUND_TO_ZERO ROUND_TO_INF INF_NAN DENORM FMA }
Half Precision Floating Point Capability: 0 { }
Native Vector Width For Char: 1
Native Vector Width For Short: 1
Native Vector Width For Int: 1
Native Vector Width For Long: 1
Native Vector Width For Float: 1
Native Vector Width For Double: 1
Native Vector Width For Half: 0
```

https://github.com/llvm/llvm-project/pull/155626