We can safely use 'gcc' on Armv7 and x64 architectures as it is

usually pointing to proper compilator for respective platform.

coupler/opc-ua-server/Makefile

-CC=$(C_COMPILER)
+CC=gcc
 CFLAGS= -I $(OPEN62541_SOURCE_HOME) 
 LDFLAGS= -L $(OPEN62541_HOME)/lib
 EXTRA_FLAGS=$(C_COMPILER_EXTRA_FLAGS)