fix/clean these Android.mk following dbort and joeo's comments
diff --git a/opengl/libagl/Android.mk b/opengl/libagl/Android.mk
index 060f3c6..d1ed82e 100644
--- a/opengl/libagl/Android.mk
+++ b/opengl/libagl/Android.mk
@@ -32,12 +32,13 @@
 
 ifneq ($(TARGET_SIMULATOR),true)
     # we need to access the private Bionic header <bionic_tls.h>
-    LOCAL_CFLAGS += -I$(LOCAL_PATH)/../../../../bionic/libc/private
+    LOCAL_C_INCLUDES += bionic/libc/private
 endif
 
 ifeq ($(LIBAGL_USE_GRALLOC_COPYBITS),1)
-    LOCAL_CFLAGS += -DLIBAGL_USE_GRALLOC_COPYBITS -I$(LOCAL_PATH)/../../../../hardware/libhardware/modules/gralloc
+    LOCAL_CFLAGS += -DLIBAGL_USE_GRALLOC_COPYBITS
     LOCAL_SRC_FILES += copybit.cpp
+    LOCAL_C_INCLUDES += hardware/libhardware/modules/gralloc
 endif
 
 LOCAL_CFLAGS += -DLOG_TAG=\"libagl\"
diff --git a/opengl/libs/Android.mk b/opengl/libs/Android.mk
index 33a1698..e1fd48b 100644
--- a/opengl/libs/Android.mk
+++ b/opengl/libs/Android.mk
@@ -20,8 +20,8 @@
 ifeq ($(TARGET_SIMULATOR),true)
 else
     LOCAL_SHARED_LIBRARIES += libdl
-    # we need to access the Bionic private header <bionic_tls.h>
-    LOCAL_CFLAGS += -I$(LOCAL_PATH)/../../../../bionic/libc/private
+    # we need to access the private Bionic header <bionic_tls.h>
+    LOCAL_C_INCLUDES += bionic/libc/private
 endif
 
 LOCAL_CFLAGS += -DLOG_TAG=\"libEGL\"
@@ -66,8 +66,8 @@
 ifeq ($(TARGET_SIMULATOR),true)
 else
     LOCAL_SHARED_LIBRARIES += libdl
-    # we need to access the Bionic private header <bionic_tls.h>
-    LOCAL_CFLAGS += -I$(LOCAL_PATH)/../../../../bionic/libc/private
+    # we need to access the private Bionic header <bionic_tls.h>
+    LOCAL_C_INCLUDES += bionic/libc/private
 endif
 
 LOCAL_CFLAGS += -DLOG_TAG=\"libGLESv1\"
@@ -95,8 +95,8 @@
 ifeq ($(TARGET_SIMULATOR),true)
 else
     LOCAL_SHARED_LIBRARIES += libdl
-    # we need to access the Bionic private header <bionic_tls.h>
-    LOCAL_CFLAGS += -I$(LOCAL_PATH)/../../../../bionic/libc/private
+    # we need to access the private Bionic header <bionic_tls.h>
+    LOCAL_C_INCLUDES += bionic/libc/private
 endif
 
 LOCAL_CFLAGS += -DLOG_TAG=\"libGLESv2\"
diff --git a/opengl/libs/EGL/Loader.cpp b/opengl/libs/EGL/Loader.cpp
index 0e0f2c2..103522e 100644
--- a/opengl/libs/EGL/Loader.cpp
+++ b/opengl/libs/EGL/Loader.cpp
@@ -165,7 +165,7 @@
     }
 
     LOG_FATAL_IF(!index && !impl && !hnd, 
-            "couldn't't find the default OpenGL ES implementation "
+            "couldn't find the default OpenGL ES implementation "
             "for default display");
     
     return (void*)hnd;
@@ -226,9 +226,7 @@
 {
     //LOGD("%s", driver);
     void* dso = dlopen(driver, RTLD_NOW | RTLD_LOCAL);
-    LOGE_IF(!dso,
-            "couldn't load <%s> library (%s)",
-            driver, dlerror());
+    LOGE_IF(!dso, "%s", dlerror());
     if (dso == 0)
         return 0;