Revert "Build: Switch mbedtls auto-patching to git am"

This reverts commit 664a449c5d093bf96064c7743e73a4b2c98e8a31.

Reason for revert: Causes build failures when git username and git email are not configured

Change-Id: I2ca2f139d629719d312f22f519599d5bdb5e7f0c
diff --git a/lib/ext/mbedcrypto/CMakeLists.txt b/lib/ext/mbedcrypto/CMakeLists.txt
index 7a28ef5..79adce1 100644
--- a/lib/ext/mbedcrypto/CMakeLists.txt
+++ b/lib/ext/mbedcrypto/CMakeLists.txt
@@ -24,7 +24,7 @@
             GIT_SHALLOW TRUE
             GIT_PROGRESS TRUE
             GIT_SUBMODULES ""
-            PATCH_COMMAND ${GIT_EXECUTABLE} am ${PATCH_FILES}
+            PATCH_COMMAND ${GIT_EXECUTABLE} apply ${PATCH_FILES}
         )
     else()
         FetchContent_Declare(mbedcrypto