sfdp: Move hints about SFDP detection into spi_prepare_sfdp()

Now that the preparation is only run when we are actually going to use
the SFDP definition, we can do the logging there, unconditionally.

Change-Id: I9abb22178799c2d2f1098f0d578ac3231983fb19
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.sourcearcade.org/c/flashprog/+/487
diff --git a/include/flash.h b/include/flash.h
index 31b4f0c..082448a 100644
--- a/include/flash.h
+++ b/include/flash.h
@@ -567,6 +567,7 @@
 int prepare_flash_access(struct flashctx *, bool read_it, bool write_it, bool erase_it, bool verify_it);
 void finalize_flash_access(struct flashctx *);
 int register_chip_restore(chip_restore_fn_cb_t func, struct flashctx *flash, uint8_t status);
+unsigned int flashprog_count_usable_erasers(const struct flashctx *);
 
 /* Something happened that shouldn't happen, but we can go on. */
 #define ERROR_NONFATAL 0x100