This is not installed on many systems. I managed to build
curl anyhow, by simple changing two lines:

cmake_minimum_required(VERSION 3.4 FATAL_ERROR)
=> cmake_minimum_required(VERSION 3.2 FATAL_ERROR)

list(APPEND CURL_LIBS OpenSSL::SSL OpenSSL::Crypto)
=> list(APPEND CURL_LIBS ssl crypto)

Are you sure, this is worth the hassle?
Alternative: if/else for version <> 3.4
(as the 'offender' is a SINGLE LINE)

---
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e6dbb73..0116ae0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -38,7 +38,7 @@
  # To check:
  # (From Daniel Stenberg) The cmake build selected to run gcc with -fPIC on my box while the plain configure script did not.
  # (From Daniel Stenberg) The gcc command line use neither -g nor any -O options. As a developer, I also treasure our configure scripts's --
-cmake_minimum_required(VERSION 3.4 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.2 FATAL_ERROR)
  set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/CMake;${CMAKE_MODULE_PATH}")
  include(Utilities)
  include(Macros)
@@ -352,7 +352,8 @@ if(CMAKE_USE_OPENSSL)
    set(USE_OPENSSL ON)
    set(HAVE_LIBCRYPTO ON)
    set(HAVE_LIBSSL ON)
-  list(APPEND CURL_LIBS OpenSSL::SSL OpenSSL::Crypto)
+#  list(APPEND CURL_LIBS OpenSSL::SSL OpenSSL::Crypto)
+  list(APPEND CURL_LIBS ssl crypto)
    set(CMAKE_REQUIRED_INCLUDES ${OPENSSL_INCLUDE_DIR})
    check_include_file("openssl/crypto.h" HAVE_OPENSSL_CRYPTO_H)
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