[ffmpeg] fix emscripten build (#29510)

* [ffmpeg] do not require nasm for wasm32 build

* addver

* Update ffmpeg.json

* .

* .

ports/ffmpeg/portfile.cmake

@@ -23,13 +23,15 @@ vcpkg_from_github(
         0022-fix-iconv.patch
 )
 
-if (SOURCE_PATH MATCHES " ")
+if(SOURCE_PATH MATCHES " ")
     message(FATAL_ERROR "Error: ffmpeg will not build with spaces in the path. Please use a directory with no spaces")
 endif()
 
-vcpkg_find_acquire_program(NASM)
-get_filename_component(NASM_EXE_PATH "${NASM}" DIRECTORY)
-vcpkg_add_to_path("${NASM_EXE_PATH}")
+if(NOT VCPKG_TARGET_ARCHITECTURE STREQUAL "wasm32")
+    vcpkg_find_acquire_program(NASM)
+    get_filename_component(NASM_EXE_PATH "${NASM}" DIRECTORY)
+    vcpkg_add_to_path("${NASM_EXE_PATH}")
+endif()
 
 if(VCPKG_TARGET_IS_WINDOWS AND NOT VCPKG_TARGET_IS_MINGW)
     #We're assuming that if we're building for Windows we're using MSVC

ports/ffmpeg/vcpkg.json

@@ -1,7 +1,7 @@
 {
   "name": "ffmpeg",
   "version": "5.1.2",
-  "port-version": 3,
+  "port-version": 4,
   "description": [
     "a library to decode, encode, transcode, mux, demux, stream, filter and play pretty much anything that humans and machines have created.",
     "FFmpeg is the leading multimedia framework, able to decode, encode, transcode, mux, demux, stream, filter and play pretty much anything that humans and machines have created. It supports the most obscure ancient formats up to the cutting edge. No matter if they were designed by some standards committee, the community or a corporation. It is also highly portable: FFmpeg compiles, runs, and passes our testing infrastructure FATE across Linux, Mac OS X, Microsoft Windows, the BSDs, Solaris, etc. under a wide variety of build environments, machine architectures, and configurations."

versions/baseline.json

@@ -2402,7 +2402,7 @@
     },
     "ffmpeg": {
       "baseline": "5.1.2",
-      "port-version": 3
+      "port-version": 4
     },
     "ffnvcodec": {
       "baseline": "11.1.5.0",

versions/f-/ffmpeg.json

@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "d471234dd831fd9a35453db450572b52291ed6ca",
+      "version": "5.1.2",
+      "port-version": 4
+    },
     {
       "git-tree": "f1ed1f91335172c9056f83efaf0c0af9a5d86d09",
       "version": "5.1.2",