Introduce arm_setup_page_tables() function

This patch introduces the arm_setup_page_tables() function to
set up page tables on ARM platforms. It replaces the
arm_configure_mmu_elx() functions and does the same thing except
that it doesn't enable the MMU at the end. The idea is to reduce
the amount of per-EL code that is generated by the C preprocessor
by splitting the memory regions definitions and page tables creation
(which is generic) from the MMU enablement (which is the only per-EL
configuration).

As a consequence, the call to the enable_mmu_elx() function has been
moved up into the plat_arch_setup() hook. Any other ARM standard
platforms that use the functions `arm_configure_mmu_elx()` must be
updated.

Change-Id: I6f12a20ce4e5187b3849a8574aac841a136de83d
diff --git a/include/plat/arm/common/plat_arm.h b/include/plat/arm/common/plat_arm.h
index 2fe0a69..3cee6ff 100644
--- a/include/plat/arm/common/plat_arm.h
+++ b/include/plat/arm/common/plat_arm.h
@@ -45,17 +45,7 @@
 /*
  * Utility functions common to ARM standard platforms
  */
-
-void arm_configure_mmu_el1(unsigned long total_base,
-			unsigned long total_size,
-			unsigned long ro_start,
-			unsigned long ro_limit
-#if USE_COHERENT_MEM
-			, unsigned long coh_start,
-			unsigned long coh_limit
-#endif
-);
-void arm_configure_mmu_el3(unsigned long total_base,
+void arm_setup_page_tables(unsigned long total_base,
 			unsigned long total_size,
 			unsigned long ro_start,
 			unsigned long ro_limit