Add static libraries to Linux amalgamation (#3699)

platform/linux/cmake/find_static_library.cmake

@@ -0,0 +1,33 @@
+function(find_static_library result_var)
+    # Usage: find_static_library(VAR_NAME NAMES name1 [name2 ...])
+    set(options)
+    set(one_value_args)
+    set(multi_value_args NAMES)
+    cmake_parse_arguments(FSL "${options}" "${one_value_args}" "${multi_value_args}" ${ARGN})
+
+    if(NOT FSL_NAMES)
+        message(FATAL_ERROR "find_static_library: NAMES argument required")
+    endif()
+
+    # Clear any previous cached result for this variable
+    unset(${result_var} CACHE)
+
+    # Temporarily force CMake to look only for .a
+    set(_old_suffixes ${CMAKE_FIND_LIBRARY_SUFFIXES})
+    set(CMAKE_FIND_LIBRARY_SUFFIXES .a)
+
+    # Invoke find_library using the caller's var name
+    find_library(${result_var} NAMES ${FSL_NAMES})
+
+    # Restore original suffix list
+    set(CMAKE_FIND_LIBRARY_SUFFIXES ${_old_suffixes})
+
+    # Check result
+    if(NOT ${result_var})
+        message(FATAL_ERROR
+            "find_static_library: could not find any of [${FSL_NAMES}] as a .a")
+    endif()
+
+    message(STATUS
+        "find_static_library: Found static [${FSL_NAMES}] -> ${${result_var}}")
+endfunction()