builder: fix wasi-libc path names on Windows with -size=full

Without this fix, wasi-libc is listed as follows:

     65       0       0       0 |      65       0 | C:\Users\Ayke\src\tinygo\tinygo\lib\wasi-libc\libc-bottom-half\sources
     14       0       0       0 |      14       0 | C:\Users\Ayke\src\tinygo\tinygo\lib\wasi-libc\libc-top-half\musl\src\exit
   1398       0       0       0 |    1398       0 | C:\Users\Ayke\src\tinygo\tinygo\lib\wasi-libc\libc-top-half\musl\src\string
   1525       0       0       0 |    1525       0 | C:\Users\Ayke\src\tinygo\tinygo\lib\wasi-libc\libc-top-half\sources

With this fix, it's identified as the wasi-libc C library:

   3002       0       0       0 |    3002       0 | C wasi-libc

Author: aykevl

builder/sizes.go

@@ -200,6 +200,11 @@ func readProgramSizeFromDWARF(data *dwarf.Data, codeOffset, codeAlignment uint64
 						// Work around a Clang bug on Windows:
 						// https://github.com/llvm/llvm-project/issues/117317
 						path = strings.ReplaceAll(path, "\\\\", "\\")
+
+						// wasi-libc likes to use forward slashes, but we
+						// canonicalize everything to use backwards slashes as
+						// is common on Windows.
+						path = strings.ReplaceAll(path, "/", "\\")
 					}
 					line := addressLine{
 						Address: prevLineEntry.Address + codeOffset,