kernel: Switch back to host openssl entirely

* OpenSSL cannot be statically linked because of
  getaddrinfo and gethostbyname calls.
* Also according to soong it's whitelisted:
  33f9529962/ui/build/paths/config.go (L98)

Change-Id: I1718bd98e7ac30d31de38c2cd3bc3e51b7100ce4

config/BoardConfigKernel.mk

@@ -116,21 +116,16 @@ ifeq ($(KERNEL_ARCH),arm64)
 endif
 
 ifeq ($(HOST_OS),darwin)
-  KERNEL_MAKE_FLAGS += C_INCLUDE_PATH=$(BUILD_TOP)/external/elfutils/libelf:$(BUILD_TOP)/prebuilts/openssl/$(HOST_OS)-x86/1.1.1/include
+  KERNEL_MAKE_FLAGS += HOSTCFLAGS="-I$(BUILD_TOP)/external/elfutils/libelf -I/usr/local/opt/openssl/include -L/usr/local/opt/openssl/lib"
 else
-  KERNEL_MAKE_FLAGS += C_INCLUDE_PATH=$(BUILD_TOP)/prebuilts/openssl/$(HOST_OS)-x86/1.1.1/include
+  KERNEL_MAKE_FLAGS += HOSTCFLAGS="-I/usr/include -I/usr/include/x86_64-linux-gnu -L/usr/lib/x86_64-linux-gnu -L/usr/lib64"
 endif
-KERNEL_MAKE_FLAGS += LIBRARY_PATH=$(BUILD_TOP)/prebuilts/openssl/$(HOST_OS)-x86/1.1.1/lib
-KERNEL_MAKE_FLAGS += HOSTCFLAGS="-L $(BUILD_TOP)/prebuilts/openssl/$(HOST_OS)-x86/1.1.1/lib"
-KERNEL_MAKE_FLAGS += HOSTLDFLAGS="-L $(BUILD_TOP)/prebuilts/openssl/$(HOST_OS)-x86/1.1.1/lib"
-
-TOOLS_PATH_OVERRIDE := LD_LIBRARY_PATH=$(BUILD_TOP)/prebuilts/openssl/$(HOST_OS)-x86/1.1.1/lib:$$LD_LIBRARY_PATH
 
 ifneq ($(TARGET_KERNEL_ADDITIONAL_FLAGS),)
   KERNEL_MAKE_FLAGS += $(TARGET_KERNEL_ADDITIONAL_FLAGS)
 endif
 
-TOOLS_PATH_OVERRIDE += \
+TOOLS_PATH_OVERRIDE := \
     PATH=$(BUILD_TOP)/prebuilts/tools-lineage/$(HOST_OS)-x86/bin:$$PATH \
     LD_LIBRARY_PATH=$(BUILD_TOP)/prebuilts/tools-lineage/$(HOST_OS)-x86/lib:$$LD_LIBRARY_PATH \
     PERL5LIB=$(BUILD_TOP)/prebuilts/tools-lineage/common/perl-base