depends: remove no longer needed patch for Boost::Process

As Boost::Process has been replaced by cpp-subprocess (PR #28981), this
patch touches an unused code part and is hence not needed anymore.

depends/packages/boost.mk

@@ -3,11 +3,6 @@ $(package)_version=1.81.0
 $(package)_download_path=https://boostorg.jfrog.io/artifactory/main/release/$($(package)_version)/source/
 $(package)_file_name=boost_$(subst .,_,$($(package)_version)).tar.bz2
 $(package)_sha256_hash=71feeed900fbccca04a3b4f2f84a7c217186f28a940ed8b7ed4725986baf99fa
-$(package)_patches=process_macos_sdk.patch
-
-define $(package)_preprocess_cmds
-  patch -p1 < $($(package)_patch_dir)/process_macos_sdk.patch
-endef
 
 define $(package)_stage_cmds
   mkdir -p $($(package)_staging_prefix_dir)/include && \