bzip2/lzma: make internal initramfs compression configurable

Impact: Avoids silent environment dependency

Make builtin initramfs compression an explicit configurable.  The
previous version would pick a compression based on the binaries which
were installed on the system, which could lead to unexpected results.
It is now explicitly configured, and not having the appropriate
binaries installed on the build host is simply an error.

Signed-off-by: Alain Knaff <alain@knaff.lu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

usr/Makefile

@@ -5,24 +5,18 @@
 klibcdirs:;
 PHONY += klibcdirs
 
-# Find out "preferred" ramdisk compressor. Order of preference is
-#  1. bzip2 efficient, and likely to be present
-#  2. gzip former default
-#  3. lzma
-#  4. none
 
-# None of the above
-suffix_y                   =
-
-# Lzma, but no gzip nor bzip2
-suffix_$(CONFIG_RD_LZMA)   = .lzma
+# No compression
+suffix_$(CONFIG_INITRAMFS_COMPRESSION_NONE)   =
 
 # Gzip, but no bzip2
-suffix_$(CONFIG_RD_GZIP)   = .gz
+suffix_$(CONFIG_INITRAMFS_COMPRESSION_GZIP)   = .gz
 
 # Bzip2
-suffix_$(CONFIG_RD_BZIP2)  = .bz2
+suffix_$(CONFIG_INITRAMFS_COMPRESSION_BZIP2)  = .bz2
 
+# Lzma
+suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZMA)   = .lzma
 
 # Generate builtin.o based on initramfs_data.o
 obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data$(suffix_y).o