feat: introduce plat_log_level variable for platforms

This patch allows individual platforms to override the log level
for the build by introducing the 'plat_log_level' variable. For
now, the variable is set to "LOG_LEVEL_INFO" to use the previous
setting.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: If317a00c7d8971aed7fbfd2178f7eff88736acd1
diff --git a/BUILD.gn b/BUILD.gn
index afd784e..cc6a78f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -84,6 +84,7 @@
     smmu_base_address = "0x2b400000"
     smmu_memory_size = "0x100000"
     enable_mte = "1"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -112,6 +113,7 @@
     smmu_memory_size = "0x100000"
     enable_vhe = "1"
     enable_mte = "1"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -133,6 +135,7 @@
     pl011_base_address = "0x1c090000"
     smmu_base_address = "0x2b400000"
     smmu_memory_size = "0x100000"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -156,6 +159,7 @@
     smmu_base_address = "0x2b400000"
     smmu_memory_size = "0x100000"
     enable_vhe = "1"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -175,6 +179,7 @@
   toolchain_args = {
     plat_ffa = "//src/arch/aarch64/plat/ffa:hypervisor"
     pl011_base_address = "0x09000000"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -195,6 +200,7 @@
     plat_ffa = "//src/arch/aarch64/plat/ffa:hypervisor"
     pl011_base_address = "0x09000000"
     enable_vhe = "1"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -214,6 +220,7 @@
     aux_base_address = "0xfe215000"
     core_freq_mhz = 500
     hftest_ctrl = "//test/hftest:ctrl_uart"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }
 
@@ -247,5 +254,6 @@
     secure_world = "1"
     pl011_base_address = "0x7ff80000"
     enable_mte = "1"
+    plat_log_level = "LOG_LEVEL_INFO"
   }
 }