Add support for generating perf maps for simple perf profiling (#6030)

* Add support for generating perf maps for simple perf profiling

* add missing enum entry in C code

* bugfix: use hexa when printing the code region's length too (thanks bjorn3!)

* sanitize file name + use bufwriter

* introduce --profile CLI flag for wasmtime

* Update doc and doc comments for new --profile option

* remove redundant FromStr import

* Apply review feedback: make_line receives a Write impl, report errors

* fix tests?

* better docs

docs/examples-profiling-vtune.md

@@ -39,7 +39,7 @@ runtime--enable runtime support based on how you use Wasmtime:
 * **C API** - call the `wasmtime_config_profiler_set` API with a
   `WASMTIME_PROFILING_STRATEGY_VTUNE` value.
 
-* **Command Line** - pass the `--vtune` flag on the command line.
+* **Command Line** - pass the `--profile=vtune` flag on the command line.
 
 
 ### Profiling Wasmtime itself
@@ -58,11 +58,11 @@ With VTune [properly installed][download], if you are using the CLI execute:
 
 ```sh
 $ cargo build
-$ vtune -run-pass-thru=--no-altstack -collect hotspots target/debug/wasmtime --vtune foo.wasm
+$ vtune -run-pass-thru=--no-altstack -collect hotspots target/debug/wasmtime --profile=vtune foo.wasm
 ```
 
 This command tells the VTune collector (`vtune`) to collect hot spot
-profiling data as Wasmtime is executing `foo.wasm`. The `--vtune` flag enables
+profiling data as Wasmtime is executing `foo.wasm`. The `--profile=vtune` flag enables
 VTune support in Wasmtime so that the collector is also alerted to JIT events
 that take place during runtime. The first time this is run, the result of the
 command is a results diretory `r000hs/` which contains profiling data for
@@ -96,13 +96,13 @@ $ rustc --target wasm32-wasi fib.rs -C opt-level=z -C lto=yes
 ```
 
 Then we execute the Wasmtime runtime (built with the `vtune` feature and
-executed with the `--vtune` flag to enable reporting) inside the VTune CLI
+executed with the `--profile=vtune` flag to enable reporting) inside the VTune CLI
 application, `vtune`, which must already be installed and available on the
 path. To collect hot spot profiling information, we execute:
 
 ```sh
 $ rustc --target wasm32-wasi fib.rs -C opt-level=z -C lto=yes
-$ vtune -run-pass-thru=--no-altstack -v -collect hotspots target/debug/wasmtime --vtune fib.wasm
+$ vtune -run-pass-thru=--no-altstack -v -collect hotspots target/debug/wasmtime --profile=vtune fib.wasm
 fib(45) = 1134903170
 amplxe: Collection stopped.
 amplxe: Using result path /home/jlb6740/wasmtime/r000hs
@@ -141,7 +141,7 @@ like:
 - Open VTune Profiler
 - "Configure Analysis" with
   - "Application" set to `/path/to/wasmtime` (e.g., `target/debug/wasmtime`)
-  - "Application parameters" set to `--vtune /path/to/module.wasm`
+  - "Application parameters" set to `--profile=vtune /path/to/module.wasm`
   - "Working directory" set as appropriate
   - Enable "Hardware Event-Based Sampling," which may require some system
     configuration, e.g. `sysctl -w kernel.perf_event_paranoid=0`