clamav: remove now obsolete iconv patch

Signed-off-by: Rosen Penev <rosenp@gmail.com>

net/clamav/patches/020-iconv.patch

@@ -1,63 +0,0 @@
---- a/CMakeLists.txt
-+++ b/CMakeLists.txt
-@@ -448,7 +448,7 @@ endif()
- 
- # libclamav feature dependencies
- if(NOT WIN32)
--    find_package(Iconv REQUIRED)
-+    find_package(Iconv)
-     # Set variable required by libclamav to use iconv
-     set(HAVE_ICONV 1)
- endif()
---- a/libclamav/CMakeLists.txt
-+++ b/libclamav/CMakeLists.txt
-@@ -536,10 +536,39 @@ if(ENABLE_SHARED_LIB)
-                 ClamAV::win32_compat
-                 wsock32 ws2_32 )
-     else()
-+        if(Iconv_FOUND)
-+            if(NOT Iconv_IS_BUILT_IN)
-+                target_link_libraries(clamav PRIVATE Iconv::Iconv)
-+                set(CMAKE_REQUIRED_LIBRARIES "Iconv::Iconv")
-+            endif()
-+        else()
-+            # Sometime the build environment is not setup
-+            # in a way CMake can find Iconv on its own by default.
-+            # But if we simply link against iconv (-liconv), the build may succeed
-+            # due to other compiler/link flags.
-+            set(CMAKE_REQUIRED_LIBRARIES "iconv")
-+            check_c_source_compiles("
-+                #include <stddef.h>
-+                #include <iconv.h>
-+                int main() {
-+                    char *a, *b;
-+                    size_t i, j;
-+                    iconv_t ic;
-+                    ic = iconv_open(\"to\", \"from\");
-+                    iconv(ic, &a, &i, &b, &j);
-+                    iconv_close(ic);
-+                }
-+                "
-+                Iconv_EXPLICITLY_AT_ENV)
-+            if(Iconv_EXPLICITLY_AT_ENV)
-+                target_link_libraries(clamav PRIVATE iconv)
-+            else()
-+                message(FATAL_ERROR "Iconv is not found, make sure to provide it in the build environment")
-+            endif()
-+        endif()
-         target_link_libraries( clamav
-             PUBLIC
-                 Threads::Threads
--                Iconv::Iconv
-                 ${CMAKE_DL_LIBS}
-                 m )
-     endif()
-@@ -556,8 +585,6 @@ if(ENABLE_SHARED_LIB)
- 
-     if(WIN32)
-         set_target_properties( clamav PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS ON )
--    else()
--        target_link_libraries( clamav PUBLIC Iconv::Iconv )
-     endif()
-     if(WIN32)
-         install( TARGETS clamav DESTINATION . COMPONENT libraries )