cmake: Rename mbedcrypto library to tfpsacrypto

Do not do the same in the make build system yet,
cmake build system only scope for this PR.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/pkgconfig/mbedcrypto.pc.in b/pkgconfig/mbedcrypto.pc.in
index 2d130ea..28b9716 100644
--- a/pkgconfig/mbedcrypto.pc.in
+++ b/pkgconfig/mbedcrypto.pc.in
@@ -7,4 +7,4 @@
 URL: @PKGCONFIG_PROJECT_HOMEPAGE_URL@
 Version: @PROJECT_VERSION@
 Cflags: -I"${includedir}"
-Libs: -L"${libdir}" -lmbedcrypto -lbuiltin -leverest -lp256m
+Libs: -L"${libdir}" -ltfpsacrypto -lbuiltin -leverest -lp256m